Method and apparatus for producing optical multilayer body

ABSTRACT

An optical laminate produced by a process for producing an anti-dazzling laminate comprising a light transparent base material and an anti-dazzling layer provided on the light transparent base material. The process includes providing the light transparent base material and forming the anti-dazzling layer having a concavoconvex shape on the light transparent base material, wherein the concavoconvex shape of the anti-dazzling layer satisfies the following requirements: Sm is not less than 100 μm and not more than 600 μm, θa is not less than 0.1 degree and not more than 1.2 degrees, and Rz is more than 0.2 μm and not more than 1 μm, wherein Sm represents the average spacing of concavoconvexes or profile irregularities in the anti-dazzling layer; θa represents the average inclination angle of the concavoconvexes or profile irregularities; and Rz represents the average roughness of the concavoconvexes or profile irregularities.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of U.S. patent applicationSer. No. 11/884,394, filed Mar. 27, 2008 and claims the benefit ofpriority from the prior Japanese Patent Applications No. 44231/2005 andNo. 95835/2005 under the Paris Convention, and, thus, the entirecontents thereof are incorporated herein by reference.

FIELD OF THE INVENTION

The present invention provides a process and apparatus for producing anoptical laminate for use in displays such as CRTs and liquid crystalpanels.

BACKGROUND OF THE INVENTION

The prevention of lowered contrast and lowered visibility caused byexternal light reflection or image reflection is required of imagedisplay devices, for example, cathode-ray tube display devices (CRTs),plasma displays (PDPs), electroluminescent displays (ELDs), or liquidcrystal displays (LCDs). Accordingly, it is common practice to provide areflection preventive laminate on the outermost surface of an imagedisplay device from the viewpoint of reducing image reflection orreflectance using the principle of light scattering or the principle ofoptical interference.

In image display devices, for example, liquid crystal displays, the useof an anti-dazzling laminate as one of antireflection laminates hashitherto been known for realizing regulating optical properties torealize excellent image displays. The anti-dazzling laminate is utilizedfor preventing a lowering in visibility as a result of external lightreflection or image reflection within image display devices. Theanti-dazzling laminate is generally realized by forming an anti-dazzlinglayer having a concavoconvex shape on a base material. In conventionalimage display devices, for example, liquid crystal displays, the use ofan anti-dazzling laminate as one antireflection laminate has hithertobeen known for regulating optical properties to realize excellent imagedisplay. The anti-dazzling laminate is utilized for preventing alowering in visibility as a result of external light reflection or imagereflection within image display devices. The anti-dazzling laminate isproduced as having a concavoconvex shape obtained by curing acomposition containing various particles, or having a concavoconvexshape formed by embossing (Japanese Patent Laid-Open No. 341070/2004).

In recent years, a demand for a higher level of definition of panelresolution has led to a higher level of fineness of the concavoconcexshape of the anti-dazzling layer. Accordingly, a concavoconvex shapehaving a broad and large curve has been regarded as unsuitable formeeting a demand for higher definition in the anti-dazzling laminatehaving the above construction and thus have not been adopted. On theother hand, when increasing the fineness of the concavoconvex shapeinvolved in higher definition of panel resolution can meet a demand forhigher definition of the panel resolution. Regarding this technique,however, it has often been pointed out that, for example, external lightis reflected from the display surface resulting in such a phenomenonthat, for example, the image display surface is seen white (whitening),or lowered contrast. When the anti-dazzling laminate is used on theimage display surface of notebook computers and the like, a certainlevel of satisfactory optical properties can be provided. When the lighttransmitted through the backside of backlight within a display istransmitted through the concavoconvex shape face of the anti-dazzlinglaminate formed on the outermost surface of the panel, however, theconcavoconvex shape functions as fine lenses which disturb the displayedpixels and the like, that is, “glare” is likely to occur. Thisunfavorable phenomenon makes it difficult to attain the effect of theanti-dazzling laminate per se. In particular, the occurrence of the“glare” increases with increasing the definition of the panelresolution, and, thus, effectively preventing this unfavorablephenomenon has been desired.

In order to eliminate this “glare,” for example, a method has beenadopted in which surface concavoconvexes are densely provided to enhancethe sharpness and, at the same time, scattering particles different fromthe resin for anti-dazzling layer formation in refractive index areadded to impart internal scattering effect to the anti-dazzlinglaminate. All of proposed methods could satisfactorily solve the problemof the “glare,” but on the other hand, they sometimes lowered thevisibility of the whole image. On the other hand, in the anti-dazzlinglaminate, the method for reducing the “glare” in high-definition panelshas been regarded as a main cause of an unfavorable phenomenon, forexample, a deterioration in contrast such as clouding caused by surfacewhitening, internal scattering effect or the like. That is, it has beenregarded that “glare prevention” and “contrast improvement” are in therelationship of tradeoff, and simultaneously meeting both therequirements is difficult. In the above methods, for example, blackcolor reproduction including glossy black feeling (wet glossy blackcolor) in on-screen display, contrast and the like have sometimes beenpoor. That is, gradation rendering of black color in a light room,particularly a black color gradation difference in low gradation, cannotbe regarded without difficulties resulting in lowered sensitivity.Specifically, black and gray colors are only recognized as a blurred andidentical color-tone black color. In particular, it can be said that ananti-dazzling laminate having better anti-glare properties has asignificantly lowered level of visibility.

Accordingly, at the present time, the development of a productionprocess (and production apparatus) for an optical laminate, which caneffectively prevent the glare of an image surface and, at the same time,can realize good black color reproduction, especially glossy blackfeeling, has been desired. In particular, a production process (andproduction apparatus) for an optical laminate, which can be used inliquid crystal displays (LCDs) as well as in other applications such ascathode ray tube display devices (CRTs), plasma displays (PDPs),fluorescent display tubes, and field emission-type displays.

SUMMARY OF THE INVENTION

At the time of the present invention, the present inventors have found aprocess and apparatus for producing an optical laminate which, whileimparting anti-dazzling properties, can realize the so-called glossyblack feeling (glossy black color) by improving the anti-glare propertyand the contrast, especially by improving black color reproduction. Thepresent invention has been made based on such finding.

Accordingly, the present invention provides a process (and apparatus)for producing an optical laminate which can realize an anti-dazzlingfunction and an excellent anti-glare property and, at the same time, canrealize image display having a high level of visibility.

Production Process

According to the present invention, there is provided a process forproducing an optical laminate comprising: a light transparent basematerial; and an anti-dazzling layer provided on the light transparentbase material, the process comprising the steps of:

providing the light transparent base material; and

forming the anti-dazzling layer having a concavoconvex shape on thelight transparent base material, wherein

the concavoconvex shape of the anti-dazzling layer satisfies thefollowing requirements:

Sm is not less than 100 μm and not more than 600 μm,

θa is not less than 0.1 degree and not more than 1.2 degrees, and

Rz is more than 0.2 μm (preferably not less than 0.35 μm) and not morethan 1 μm (preferably not more than 0.9 μm),

wherein Sm represents the average spacing of concavoconvexes or profileirregularities in the anti-dazzling layer; θa represents the averageinclination angle of the concavoconvexes (or profile irregularities);and Rz represents the average roughness of the concavoconvexes (orprofile irregularities).

Production Apparatus

According to another aspect of the present invention, there is providedan apparatus for producing an optical laminate comprising: a lighttransparent base material and an anti-dazzling layer provided on thelight transparent base material, the apparatus comprising:

a feed part for feeding the light transparent base material and theanti-dazzling layer having a concavoconvex shape; and

a forming part for forming the anti-dazzling layer on the lighttransparent base material, wherein

the concavoconvex shape of the anti-dazzling layer satisfies thefollowing requirements:

Sm is not less than 100 μm and not more than 600 μm,

θa is not less than 0.1 degree and not more than 1.2 degrees, and

Rz is more than 0.2 μl (preferably not less than 0.35 μm) and not morethan 1 μm (preferably not more than 0.9 μm),

wherein Sm represents the average spacing of concavoconvexes or profileirregularities in the anti-dazzling layer; θa represents the averageinclination angle of the concavoconvexes (or profile irregularities);and Rz represents the average roughness of the concavoconvexes (orprofile irregularities).

The production process and production apparatus according to the presentinvention can provide an optical laminate which can realize excellentanti-dazzling properties and black color reproduction having glossyblack feeling, can realize a high level of sharpness and excellentanti-glare property, contrast, and letter blurring preventive property,and can be used in various displays. In particular, the process forproducing an optical laminate according to the present invention canprovide an optical laminate which is significantly improved in blackcolor gradation rendering (glossy black color reproduction), which couldnot have been realized by the conventional anti-dazzling laminatewithout difficulties. More specifically, it is possible to provide anoptical laminate which, in an image in movie display, can rendergradation substantially comparable with a conventional display providedwith a laminate comprising a clear hard coat layer free from anyconcavoconvex shape and an antireflection layer provided on the clearhard coat layer and, at the same time, can realize a good sharpness ofthe contour of letters and can prevent scintillation. In a preferredembodiment of the present invention, the provision of an optional layersuch as a surface modifying layer or a low-refractive index layer on theanti-dazzling layer means that the surface of the concavoconvex shapeconstituting the anti-dazzling layer is sealed by the optional layer,and, thus, a large and smooth desired concavoconvex shape can berealized. Further, various functions such as antistatic property,refractive index regulation, and contamination prevention can beimparted to the optical laminate. When an optional layer such as asurface modifying layer or a low-refractive index layer is provided onthe anti-dazzling layer, the surface concavoconvex shape of the optionallayer such as the surface modifying layer or the low-refractive indexlayer conforms to the optical property values of the surfaceconcavoconvex shape of the anti-dazzling layer according to the presentinvention. That is, in the optical laminate according to the presentinvention, the concavoconvex shape of the outermost surface conforms tothe optical property values of the surface concavoconvex shape of theanti-dazzling layer specified in the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graph showing the relationship between the reflection Yvalue and the surface haze value for an optical laminate.

FIG. 2 is a graph showing the relationship between θa and Sm for anoptical laminate.

FIG. 3 is a diagram showing a production process of an optical laminateaccording to the present invention.

FIG. 4 is a schematic diagram showing a production apparatus accordingto the present invention.

FIG. 5 is a schematic diagram showing a production apparatus accordingto the present invention.

FIG. 6 is a schematic diagram showing a production apparatus accordingto the present invention.

FIG. 7 is an optical photomicrograph of a surface shape of each of anoptical laminate according to the present invention and a conventionalanti-dazzling optical laminate.

FIG. 8 is a photograph of an optical laminate according to the presentinvention taken by three-dimensional measurement under AFN.

FIG. 9 is a photograph of a conventional optical laminate taken bythree-dimensional measurement under AFN.

DETAILED DESCRIPTION OF THE INVENTION Definition

Terms used in the present specification (working examples and the like)will be defined as follows.

1) Ten-point Average Roughness (Rz)

The average roughness is measured by measuring the surface shape as atwo-dimensional or three-dimensional profile. In fact, the measurementin this case is carried out under a scanning probe microscope or anatomic force microscope. It is generally difficult to objectivelycompare curves per se, and, hence, various roughness indexes arecalculated based on the profile curve data. Accordingly, in the presentinvention, the ten-point average roughness (Rz) is calculated using theabove measurement results and is expressed in terms of the sum of theaverage value of absolute values of the highest five deviation valuesand the average value of absolute values of the lowest five deviationvalues among deviation values determined from average values.

2) Average Spacing of Profile Irregularities (Concavoconvexes) Sm (μm)and Average Inclination Angle θa

The anti-dazzling layer constituting the optical laminate according tothe present invention has a concavoconvex shape. Sm (μm) represents theaverage spacing of concavoconvexes (profile irregularities) of theanti-dazzling layer, and θa (degree) represents the average inclinationangle of the concavoconvex part. Sm (μm) and θa (degree) may be definedas described in an instruction manual (revised on Jul. 20, 1995) of asurface roughness measuring device (model: SE-3400, manufactured byKosaka Laboratory Ltd.). θa (degree) represents the angle mode, and,when the inclination is Δa in terms of aspect ratio, θa (degree) isdetermined by θa (degree)=1/tanΔa=1/(sum of values of difference betweenthe lowest part and the highest part in each concavoconvex(corresponding to the height of each convex part)/reference length). The“reference length” is the same as in the following measuring conditions1.

When the parameters (Sm, θa, and Rz) representing the surface roughnessof the optical laminate according to the present invention may bemeasured, for example, with the above surface roughness measuring deviceunder the following measurement conditions. This measuring method isfavorable in the present invention.

Measuring Conditions

1) Tracer in Surface Roughness Detector:

-   -   Model/SE2555N (standard 2 μm), manufactured by Kosaka Laboratory        Ltd. (radius of curvature in tip 2 μm/apex angle: 90        degrees/material: diamond)

2) Measuring Conditions for Surface Roughness Measuring Device:

-   -   Reference length (cut-off value of roughness curve λc): 2.5 mm    -   Evaluation length (reference length (cut-off value λc)×5): 12.5        mm    -   Feed speed of tracer: 0.5 mm/sec

ψ∂Rz/Sm

The ratio ψ between the average roughness Rz of concavoconvexes and theaverage spacing Sm of concavoconvexes is defined by ψ∂Rz/Sm. The ratiobetween the average roughness Rz of concavoconvexes and the averagespacing Sm of concavoconvexes can be used as an index for indicating thegradient of the inclination of the concavoconvexes. The ratio ψ betweenthe average roughness Rz of concavoconvexes and the average spacing Smof concavoconvexes is defined by ψ∂Rz/Sm. The ratio between the averageroughness Rz of concavoconvexes and the average spacing Sm ofconcavoconvexes can be used as an index for indicating the tilt angle ofthe inclination of the concavoconvexes.

3) Reflection Y Value

The reflection Y value is a value indicating a luminous reflectancedetermined by measuring 5-degree regular reflectance in a wavelengthrange of 380 to 780 nm with a spectrophotometer MPC 3100 manufactured byShimadzu Seisakusho Ltd. and then converting the reflectance values tolightness which can be perceived by the human eye with a software(incorporated in MPC 3100). The 5-degree regular reflectance is measuredin such a state that, in order to prevent the backside reflection of thefilm as the optical laminate, a black tape (manufactured by TeraokaSeisakusho Co., Ltd.) is applied to the side remote from the film faceto be measured.

4) Haze Value, Total Light Transmittance, 60-degree Gloss, andTransmission Sharpness

The haze value may be measured according to JIS K 7136. Areflection-transmittance meter HR-100 (Murakami Color ResearchLaboratory) may be mentioned as an instrument used for the measurement.The total light transmittance of the anti-dazzling laminate may bemeasured with the same measuring device as in the haze value accordingto JIS K 7361. The haze and total light transmittance are measured insuch a state that the coated face is directed to a light source. The60-degree gloss can be measured with a precision gloss meter (GM-26D,manufactured by Murakami Color Research Laboratory) according to JIS Z8741. The 60-degree gloss is measured in such a state that, in order toeliminate the influence of backside reflection of a sample, a doubleface adhesive tape (manufactured by Teraoka Seisakusho Co., Ltd.) isapplied to the backside of a sample and a black lid of the measuringdevice. The transmission sharpness is expressed in terms of the total ofnumerical values obtained by measurement with four types of opticalcombs (0.125 mm, 0.5 mm, 1 mm, and 2 mm) with an image clarity measuringdevice (stock number; “ICM-1DP”, manufactured by Suga Test InstrumentsCo., Ltd.) according to JIS K 7105.

5) Definition of Surface Haze

The term “surface haze” as used herein is determined as follows. Apentaerythritol triacrylate or other resin (including resin componentssuch as monomers or oligomers) is diluted with toluene or the like to asolid content of 60%, and the diluted solution is coated with a wire baronto concavoconvexes of the anti-dazzling layer to a thickness on a dryfilm basis of 8 μm, whereby the surface concavoconvexes of theanti-dazzling layer are rendered flat. In this case, when the recoatingagent is likely to be repelled and less likely to wet the anti-dazzlinglayer due to the presence of a leveling agent in the composition foranti-dazzling layer formation, a method may be adopted in which theanti-dazzling film is previously rendered hydrophilic by saponification.The saponification is carried out by immersing the anti-dazzling film ina 2 mol/liter NaOH (or KOH) solution (55° C.) for 3 min, washing thefilm with water, completely removing water droplets with a Kimwipe, andthen drying the film in an oven (50° C.) for one min. The film having aflattened surface does not have any haze derived from surfaceconcavoconvexes but has only an internal haze. This haze can bedetermined as an internal haze. The value obtained by subtracting theinternal haze from the original film haze (overall haze) is determinedas a haze (a surface haze) attributable only to surface concavoconvexes.

6) Thickness of Anti-dazzling Layer

The thickness of the anti-dazzling layer refers to a part extended fromthe interface, between the base material on its display surface side andthe outermost surface of the anti-dazzling concavoconvex in contact withthe air. In the part extended from the base material surface to theoutermost surface, the anti-dazzling layer has either a single layer ora multilayer structure comprising a surface modifying layer and otheroptical function layers stacked onto the anti-dazzling layer.

Method for Measuring Layer Thickness

The cross section of the optical laminate was subjected to transmissionobservation under a confocal laser microscope (LeicaTCS-NT, manufacturedby Leica: magnification “100 to 300 times) to determine whether or notthe interface was present, and the results were evaluated according tothe following criteria. Specifically, in order to provide ahalation-free sharp image, a wet objective lens was used in a confocallaser microscope, and about 2 ml of an oil having a refractive index of1.518 was placed on an optical laminate, followed by observation todetermine the presence or absence of the interface. The oil was used toallow the air layer between the objective lens and the optical laminateto disappear.

Measurement Procedure

1: The average thickness of the layer was measured by observation undera laser microscope.

2: The measurement was carried out under the following conditions.

3: For one image plane, the layer thickness from the base material tothe maximum profile peak (convex) part was measured for one point, andthe layer thickness from the base material to the minimum valley(concave) part was measured for one point. That is, the layer thicknesswas measured for two points in total for one image plane. Thismeasurement was carried out for five image planes, that is, 10 points intotal, and the average value was determined.

Production Process

The concavoconvex shape of the anti-dazzling layer formed by theproduction process according to the present invention is formed ashaving optical properties which will be described later in connectionwith “optical laminate.” In an embodiment of the present invention, theanti-dazzling layer in the optical laminate produced by the processaccording to the present invention satisfies the following requirements:

Sm is not less than 100 μm and not more than 600 μm,

θa is not less than 0.1 degree and not more than 1.2 degrees, and

Rz is more than 0.2 m and not more than 1

wherein Sm represents the average spacing of concavoconvexes (or profileirregularities) in the anti-dazzling layer; θa represents the averageinclination angle of the concavoconvexes (or profile irregularities);and Rz represents the average roughness of the concavoconvexes (orprofile irregularities).

First Production Process

According to the present invention, there is provided a first processfor producing an optical laminate comprising: a light transparent basematerial; and an anti-dazzling layer provided on the light transparentbase material, the process comprising the steps of:

providing the light transparent base material; and

forming the anti-dazzling layer having a concavoconvex shape on thelight transparent base material.

The production process of an optical laminate (HG) according to thepresent invention will be described with reference to FIG. 3. FIG. 3 isa cross-sectional view of an optical laminate according to the presentinvention. In the production process of present invention, a lighttransparent base material 2 is first provided. Next, an anti-dazzlinglayer 4 is formed on the upper surface of the light transparent basematerial 2 to produce the optical laminate. In the present invention,various methods for anti-dazzling layer formation can be utilized.Preferred methods are as follows.

Second Production Process

The second production process according to the present invention is thesame as the first production process of the present invention, exceptthat an anti-dazzling layer on which a concavoconvex shape has beenpreviously formed is provided on the light transparent base material.The second production process may be described in more detail withreference to FIG. 3. Specifically, an anti-dazzling layer 4 on which aconcavoconvex shape has been previously formed is provided on a lighttransparent base material 1. Preferably, the anti-dazzling layer 4 isformed with the aid of an easy-adhesion layer such as an adhesive agent(layer) or a primer. Alternatively, a method may also be adopted inwhich a previously formed anti-dazzling layer is formed onto the uppersurface of the light transparent base material 2 through an adhesive(agent) layer and the adhesive (agent) layer is then subjected to curingor the like.

Third Production Process

The third production process according to the present invention is thesame as the first production process of the present invention, exceptthat an anti-dazzling layer is formed on the light transparent basematerial and a concavoconvex shape is formed on the surface of theanti-dazzling layer. In a preferred embodiment of the present invention,the concavoconvex shape is formed by embossing treatment using a moldhaving a reversed concavoconvex shape in relation to the concavoconvexshape in the anti-dazzling layer. The concavoconvex shape formation maybe described in detail with reference to FIG. 3. Specifically, ananti-dazzling layer 4 having a concavoconvex shape can be formed byforming an anti-dazzling layer on a light transparent base material 1and then forming a concavoconvex shape on the surface of theanti-dazzling layer. In a preferred embodiment of the present invention,the concavoconvex shape may be formed in the anti-dazzling layer 4 byusing a mold having a reversed concavoconvex shape in relation to theconcavoconvex shape in the anti-dazzling layer 4. The anti-dazzlinglayer 4 per se may be formed in the same manner as in the secondproduction process.

Fourth Production Process

The fourth production process according to the present invention is thesame as the first production process according to the present invention,except that a composition for an anti-dazzling layer is applied onto thelight transparent base material to form the above anti-dazzling layerhaving a concavoconvex shape. In a preferred embodiment of the presentinvention, for example, a method may be adopted in which the compositionfor an anti-dazzling layer is subjected to curing or the like in theformation of the anti-dazzling layer having a concavoconvex shape. InFIG. 3, the anti-dazzling layer 4 contains a resin and fine particles.The fine particles may be those having an identical shape or averageparticle diameter or the same or different shape or average particlediameter, or may be aggregation-type fine particles. On the other hand,in the present invention, the anti-dazzling layer may also be formed byusing a polymer or resin only. The details of the method foranti-dazzling layer 4 formation may be the same as described below inconnection with “anti-dazzling layer.”

Fifth Production Process

The fifth production process is a process for producing an opticallaminate, comprising: a light transparent base material; and ananti-dazzling layer provided on the light transparent base material, theprocess comprising the steps of:

providing the light transparent base material;

introducing the light transparent base material into a mold having areversed concavoconvex shape in relation to the concavoconvex shape ofthe surface of the anti-dazzling layer; and

applying a composition for an anti-dazzling layer to the mold to form ananti-dazzling layer having a concavoconvex shape on the lighttransparent base material.

Optional Process

In a preferred embodiment of the present invention, there is alsoprovided a production process in which a surface modifying layer 6 isformed on an anti-dazzling layer 4. In a more preferred embodiment ofthe present invention, in an optical laminate to be disposed on theoutermost surface of a display device, lowering the reflection (areduction in reflectance) of the optical laminate utilizing theprinciple of optical interferences is preferred from the viewpoint ofpreventing, for example, contrast deterioration or visibilitydeterioration by external light reflection or image reflection. Forexample, there is proposed a production process in which alow-refractive index layer 8 having a lower refractive index than therefractive index of the anti-dazzling layer 4 or the surface modifyinglayer 6 is formed on the surface of the surface modifying layer 6.

Production Apparatus

The concavoconvex shape of the anti-dazzling layer formed by theproduction apparatus according to the present invention is formed ashaving optical properties which will be described later in connectionwith “optical laminate.” In a preferred embodiment of the presentinvention, the concavoconvex shape of the anti-dazzling layer in theoptical laminate produced by the production apparatus according to thepresent invention satisfies the following requirements:

Sm is not less than 100 μm and not more than 600 μm,

θa is not less than 0.1 degree and not more than 1.2 degrees, and

Rz is more than 0.2 μm and not more than 1

wherein Sm represents the average spacing of concavoconvexes or profileirregularities in the anti-dazzling layer; θa represents the averageinclination angle of the concavoconvexes (or profile irregularities);and Rz represents the average roughness of the concavoconvexes (orprofile irregularities).

First Production Apparatus

The first production apparatus according to the present invention is anapparatus for producing an optical laminate comprising a lighttransparent base material and an anti-dazzling layer provided on thelight transparent base material, the apparatus comprising:

a feed part for feeding the light transparent base material and theanti-dazzling layer having a concavoconvex shape; and

a forming part for forming the anti-dazzling layer on the lighttransparent base material.

Any schematic diagram of this apparatus is not specifically shown, andthe construction of the first production apparatus may be the same asthat of the second production apparatus, described below, the firstembodiment of which is schematically shown in FIG. 4, except that aroller emboss 27 and a roller 25 c are not provided.

Second Production Apparatus

The second production apparatus according to the present invention is anapparatus for producing an optical laminate comprising a lighttransparent base material and an anti-dazzling layer provided on thelight transparent base material, the apparatus comprising:

a feed part for feeding the light transparent base material and theanti-dazzling layer; and

a forming part for forming the anti-dazzling layer on the lighttransparent base material and forming a concavoconvex shape in theanti-dazzling layer.

The second production apparatus will be briefly described with referenceto FIG. 4. FIG. 4 is a schematic diagram of the second productionapparatus according to the present invention. A light transparent basematerial 21 is fed through a roller 25 a as a feed part, and ananti-dazzling layer (free from a concavoconvex shape) 23 is fed througha roller 25 b as the feed part. The fed light transparent base material21 and anti-dazzling layer 23 are integrated with each other by theroller 25 a and the roller 25 b. In a preferred embodiment of thepresent invention, a feed part for feeding an adhesive agent (layer) maybe provided. In this case, the light transparent base material 21 andthe anti-dazzling layer 23 are integrated with each other through theadhesive agent (layer) fed from the feed part. The integrated lighttransparent base material 21 and anti-dazzling layer 23 are introducedinto a roller emboss 27 having a reversed concavoconvex shape 22 inrelation to the concavoconvex shape to be imparted to the anti-dazzlinglayer. The integrated light transparent base material 21 andanti-dazzling layer 23 is held between the roller emboss 27 and theroller 25 c to form a desired concavoconvex shape in the anti-dazzlinglayer 23 and thus to form an optical laminate 29. The optical laminate29 thus formed is supplied as a product through a roller 25 d.

In a preferred embodiment of the present invention, the forming partcomprises a mold having a reversed concavoconvex shape in relation tothe concavoconvex shape in the anti-dazzling layer. Besides the rolleremboss 27, a flat-type emboss plate may be used. Emboss treatmentmethods, roller emboss, flat-type emboss plates and the like may be thesame as described below in connection with the fourth productionapparatus according to the present invention.

Third Production Apparatus

The third production apparatus according to the present invention is anapparatus for producing an optical laminate comprising a lighttransparent base material and an anti-dazzling layer provided on thelight transparent base material, the apparatus comprising:

a feed part for feeding the light transparent base material;

an application part for applying a composition for an anti-dazzlinglayer on the light transparent base material; and

a forming part for curing the composition for an anti-dazzling layer toform the anti-dazzling layer having a concavoconvex shape.

The third production apparatus according to the present invention willbe briefly described with reference to FIG. 5. FIG. 5 is a schematicdiagram of the third production apparatus according to the presentinvention. A light transparent base material 31 is held between rollers35 a and 35 b as the feed part and is fed. A coating head 33 is providedbehind the rollers 35 a and 35 b as the feed part, and a composition 34for an anti-dazzling layer is fed from a liquid reservoir through a pipe36. The fed composition 34 for an anti-dazzling layer is fed through aslit 39 open toward the lower part of the coating head 33. Thecomposition 34 for an anti-dazzling layer is applied through the slit 39onto the fed light transparent base material 31 to form a layer of thecomposition 34 for an anti-dazzling layer. Thereafter, curing treatmentis carried out by a curing device 38 provided behind the coating head33, whereby the composition 34 for an anti-dazzling layer is cured toform a desired concavoconvex shape on the anti-dazzling layer 37. Theoptical laminate comprising the cured anti-dazzling layer 37 provided onthe light transparent base material 41 is moved and passed through aroller 25 d to produce an optical laminate.

Fourth Production Apparatus

The fourth production apparatus according to the present invention is anapparatus for producing an optical laminate comprising a lighttransparent base material and an anti-dazzling layer provided on thelight transparent base material, the apparatus comprising:

a feed part for feeding the light transparent base material;

a mold having a reversed concavoconvex shape in relation to theconcavoconvex shape of the surface of the anti-dazzling layer providedon the light transparent base material;

an introduction part for introducing the composition for ananti-dazzling layer into the mold; and

a forming part for curing the composition for an anti-dazzling layer toform the anti-dazzling layer having a concavoconvex shape.

One embodiment of the fourth production apparatus will be brieflydescribed with reference to FIG. 6. FIG. 6 is a schematic diagram of thefourth production apparatus (embossing apparatus 40) according to thepresent invention. A light transparent base material 41 is fed to anemboss roller 47 through a nip roller 45 a as the feed part. A reversedconcavoconvex shape 42 in relation to the desired concavoconvex shape ofthe anti-dazzling layer is provided on the surface of the emboss roller47. A coating head 43 is provided on the lower part of the emboss roller47, and an a composition 44 for an anti-dazzling layer is fed through apipe 46 from a liquid reservoir (not shown). The fed composition 44 foran anti-dazzling layer is fed through a slit 49 open toward the upperpart of the coating head 43. The composition 44 for an anti-dazzlinglayer is applied to the emboss roller 47 on its surface having aconcavoconvex shape 42. The emboss roller 47 is then rotated (in adirection indicated by an arrow in the drawing). Consequently, the lighttransparent base material 41 and the composition 44 for an anti-dazzlinglayer are brought into intimate contact with each other between theconcavoconvex shape 42 in the emboss roller 47 and the nip roller 45 aas the feed part. In a preferred embodiment of the present invention,instead of the formation of the light transparent base material 41 afterthe application of the composition 44 for an anti-dazzling layer ontothe concavoconvex shape 42, a method may be adopted in which, whilewinding the light transparent base material 41 around the emboss roller47, the composition 44 for an anti-dazzling layer is fed into betweenthe light transparent base material 41 and the emboss roller 47 to bringthe light transparent base material 41 and the layer of the composition44 for an anti-dazzling layer into contact with each other. The assemblyin which the light transparent base material 41 and the layer of thecomposition 44 for an anti-dazzling layer have been brought intointimate contact with each other is moved onto the upper part of theemboss roller 47, and curing treatment is carried out by a curing device48 provided above the emboss roller 47, whereby the layer of thecomposition 44 for an anti-dazzling layer is cured and integrated withthe upper part of the light transparent base material 41. The opticallaminate comprising the cured layer of the composition 44 for ananti-dazzling layer provided on the light transparent base material 41is moved upon the rotation of the emboss roller 47 and is separated fromthe emboss roller 47 by a peel-off roller 45 b to produce an opticallaminate comprising an anti-dazzling layer having a concavoconvex shape.

Embossing

The fourth production apparatus according to the present invention isadvantageous in that an optical laminate provided with an anti-dazzlinglayer having a desired concavoconvex shape formed without incorporatingfine particles can be produced. In the present invention, theconcavoconvex shape may be formed by an emboss method in which a formedanti-dazzling layer or an anti-dazzling layer which is in the course offormation thereof is embossed by an emboss plate (preferably a rolleremboss), and, if necessary, curing treatment is carried out, forexample, by heating. In a preferred embodiment of the present invention,a method is adopted which comprises providing a concavoconvex moldhaving a surface with a reversed concavoconvex shape in relation to thedesired concavoconvex shape, applying a composition, for ananti-dazzling layer, having a high level of curability onto the lighttransparent base material, and then subjecting the assembly to curing tointegrate the light transparent base material with the anti-dazzlinglayer having a concavoconvex shape and thus to produce an opticallaminate. In the present invention, a method may be adopted in which acomposition for an anti-dazzling layer is first applied followed byembossing with a mold having a concavoconvex mold shape. Alternatively,a method may also be adopted in which a composition for an anti-dazzlinglayer is supplied to the interface of a light transparent base materialand a mold having a concavoconvex shape to allow the composition for ananti-dazzling layer to be interposed between the mold having aconcavoconvex shape and the light transparent base material and to theformation of the concavoconvex shape and the formation of theanti-dazzling layer simultaneously. In a preferred embodiment of thepresent invention, in addition to the emboss roller, a flat emboss platemay also be used.

The mold surface having a concavoconvex shape formed, for example, in anemboss roller or a flat emboss plate may be formed by various methods,specifically by a sandblasting method or a bead shot method. Theanti-dazzling layer formed using an emboss plate (an emboss roller)formed by the sandblast method has such a shape that a number ofconcaves (on the other hand, downward convexed cross section) aredistributed on the upper side. On the other hand, the anti-dazzlinglayer formed using an emboss plate (an emboss roller) formed by the beadshot method has such a shape that a number of convexes (on the otherhand, upward convexed cross section) are distributed on the upper side.

When the average roughness of concavoconvexes formed on the surface ofthe anti-dazzling layer is identical, the anti-dazzling layer in which anumber of convexes are distributed on its upper side is regarded ascausing a lower level of reflection of a lighting equipment in a room orthe like as compared with the anti-dazzling layer in which a number ofconcaves are distributed on its upper side. Accordingly, in a preferredembodiment of the present invention, the concavoconvex shape of theanti-dazzling layer is formed by utilizing a concavoconvex mold having ashape identical to the concavoconvex shape of the anti-dazzling layer bya bead shot method. The concavoconvex shape formed by this concavoconvexmold is such that the proportion of the upward convexed cross-sectionalshape part is larger than that of the downward convexed cross-sectionalshape part. In another preferred embodiment of the present invention,the concavoconvex shape of the anti-dazzling layer is formed byutilizing a concavoconvex mold having a shape, which is reverse to theconcavoconvex shape of the anti-dazzling layer, formed by the bead shotmethod. The concavoconvex shape formed by this concavoconvex mold issuch that the proportion of the downward convexed cross-sectional shape(that is, concave) part is larger than that of the upward convexedcross-sectional shape (that is, convex) part.

Mold materials for forming the concavoconvex mold face usable hereininclude metals, plastics, woods, or composites thereof. Example ofpreferred mold materials in the present invention are chromium as ametal from the viewpoints of strength and abrasion resistance uponrepeated use, and are iron emboss plates (emboss rollers) having asurface plated with chromium, for example, from the viewpoints of costeffectiveness.

Specific examples of particles (beads) sprayed in the formation of theconcavoconvex mold by the sandblast or bead shot method includeinorganic particles such as metal particles, silica, alumina, or glass.The particle size (diameter) of these particles is preferably about 100μm to 300 μm. In spraying these particles against the mold material, amethod may be adopted in which these particles, together with a highspeed gas, are sprayed. In this case, a proper liquid, for example,water or the like may be used in combination with the particles. In thepresent invention, preferably, the concavoconvex mold having aconcavoconvex shape is plated with chromium or the like to improve thedurability during use of the mold and is preferred from the viewpointsof film hardening and corrosion prevention.

Optical Laminate

The optical laminate according to the present invention simultaneouslyhas anti-dazzling properties and excellent black color reproduction andcontrast. In the present invention, the optical laminate is referred toas a half glare optical laminate (HG). HG has both properties of aconventional anti-glare optical laminate (AG) having excellentanti-dazzling properties and properties of an optical laminate (AR)comprising a clear hard coat (glare) layer provided with alow-refractive index layer and having excellent black color reproductionand contrast. Specifically, the provision of a surface modifying layerconsidered as one of methods for half glare optical laminate (HG)formation on the anti-glare optical laminate (AG) renders theconcavoconvex shape of the anti-dazzling layer smooth, and, further,imparting a surface roughness parameter similar to the anti-glare (AG)can realize the production of an anti-dazzling laminate having a veryhigh level of glossy black feeling while imparting satisfactoryanti-dazzling properties. Accordingly, the details of the opticallaminate (HG) according to the present invention will be described whilecomparing the conventional AR and AG.

FIG. 1 is a diagram showing the relationship between the surface hazevalue (%) and the reflection Y value (%) in the optical laminate. InFIG. 1, the conventional AR belongs to an area in which the surface hazevalue is less than about 0.3%, specifically an area on the left sidefrom the ruled line indicated by a reference numeral 1. On the otherhand, the conventional AG belongs to an area where the surface hazevalue is approximately 4.0% to 25.0% (generally not less than 10.0%) andthe reflection Y value is approximately 1.0 to 4.5, specifically an areasurrounded by a reference numeral 5 (generally a right side area in thearea surrounded by the reference numeral 5). On the other hand, theoptical laminate (HG) according to the present invention belongs to anarea where the surface haze value is approximately not less than 0.2%and not more than 3.5% (preferably not more than 3.0) and the reflectionY value is approximately not less than 0.5 and not more than 4.5,specifically an area surrounded by a reference numeral 3.

The optical properties of the optical laminate produced by theproduction process according to the present invention will be describedwith reference to FIG. 2. FIG. 2 is a diagram showing the relationshipbetween the average inclination angle θa (in degree) in theconcavoconvexes part of the anti-dazzling layer in the optical laminateand the average spacing Sm (μm) of the concavoconvexes. As can be seenfrom FIG. 2, in the conventional AG, specifically, AG having a θa valueof not less than 1.5 degrees and not more than 2.5 degrees and an Smvalue of approximately more than 30 μm and not more than 200 μm (an areaindicated by a reference numeral 9), that is, one falling within thearea indicated by a reference numeral 11, has been regarded as apreferred AG. On the other hand, in the optical laminate (HG) accordingto the present invention, the θa value is more than 0.1 degree and notmore than 1.2 degrees. Preferably, the lower limit of the θa value is0.3 degree, and the upper limit of the θa value is 0.6 degree. The Smvalue is approximately not less than 100 μm and not more than 600 μm.Preferably, the lower limit of the Sm value is 120 μm, and the upperlimit of the Sm value is 400 μm. Specifically, an optical laminatefalling within an area indicated by a reference numeral 7 is utilized.The Rz value of the optical laminate according to the present inventionis more than 0.2 μm (preferably not less than 0.35 μm) and not more than1.2 μm (preferably not more than 1 μm, more preferably not more than 0.9μm).

1. Anti-dazzling Layer

In the production process according to the present invention, theanti-dazzling layer may be formed, for example, by stacking a previouslyformed anti-dazzling layer onto the surface of the optical laminate.Additional methods for forming the anti-dazzling layer on the surface ofthe optical laminate in the present invention include 1) a method inwhich an anti-dazzling layer having a concavoconvex shape is formedusing a composition for an anti-dazzling layer comprising fine particlesadded to a resin, 2) a method in which an anti-dazzling layer having aconcavoconvex shape is formed using a composition for an anti-dazzlinglayer containing only a resin or the like without the addition of fineparticles, and 3) a method in which an anti-dazzling layer is formed byusing treatment for forming a concavoconvex shape. In the presentinvention, when an anti-dazzling layer is previously formed, theanti-dazzling layer may be one formed by any one of the above methods 1)to 3).

The thickness H μm of the anti-dazzling layer formed by the productionprocess according to the present invention is not less than 0.5 μm andnot more than 27 μm (preferably not more than 12 μm). Preferably, thelower limit of the thickness of the anti-dazzling layer is 1 μm, and theupper limit of the thickness of the anti-dazzling layer is 7 μm.

Method for Anti-dazzling Layer Formation Using Composition forAnti-dazzling Layer, Comprising Resin Containing Fine Particles

Method for Anti-dazzling Layer Formation

The anti-dazzling layer may be formed by mixing fine particles oraggregation-type fine particles (preferably first fine particles andsecond fine particles) and the resin with a proper solvent to give acomposition for an anti-dazzling layer and coating the composition ontoa light transparent base material. Suitable solvents used in this caseinclude alcohols such as isopropyl alcohol, methanol, and ethanol;ketones such as methyl ethyl ketone (MEK), methyl isobutyl ketone(MIBK), and cyclohexanone; esters such as methyl acetate, ethyl acetate,and butyl acetate; halogenated hydrocarbons; aromatic hydrocarbons suchas toluene and xylene; or their mixtures.

Methods usable for coating the composition for anti-dazzling layer ontothe light transparent base material include coating methods such as rollcoating, Mayer bar coating, and gravure coating. After coating of thecomposition for an anti-dazzling layer, the coating is dried and curedby ultraviolet irradiation. Specific examples of ultraviolet sourcesinclude light sources, for example, ultra-high-pressure mercury lamps,high-pressure mercury lamps, low-pressure mercury lamps, carbon arclamps, black light fluorescent lamps, and metal halide lamps. Regardingthe wavelength of the ultraviolet light, a wavelength range of 190 to380 nm may be used. Specific examples of electron beam sources includevarious electron beam accelerators, for example, Cockcroft-Waltonaccelerators, van de Graaff accelerators, resonance transformeraccelerators, insulated core transformer accelerators, linearaccelerators, Dynamitron accelerators, and high-frequency accelerators.The resin is cured, and the fine particles in the resin are fixed toform a desired cancavoconvex shape on the outermost surface of theanti-dazzling layer.

Fine Particles

The fine particles may be in a spherical, for example, truly spherical,elliptical or acicular form, preferably in a truly spherical form. Inthe present invention, the average particle diameter R (μm) of the fineparticles is not less than 1.0 μm and not more than 20 μm. Preferably,the upper limit is 15.0 μm, and the lower limit is 3.5 μm.

In the present invention, not less than 80% (preferably not less than90%) of the whole fine particles is accounted for by fine particleshaving an average particle diameter distribution of R±1.0 (preferably0.3) μm. When the average particle diameter distribution of the fineparticles falls within the above-defined range, the evenness of theconcavoconvex shape of the anti-dazzling laminate can be rendered goodand, at the same time, scintillation and the like can be effectivelyprevented. Further, the anti-dazzling layer may further comprise, inaddition to the fine particles, second fine particles or third fineparticles or a combination of a plurality of types of fine particlesdifferent from the fine particles in average particle diameter. Forexample, for small fine particles of which the average particle diameterR (μm) is approximately the lower limit value, i.e., about 3.5 μm, aconcavoconvex layer can be efficiently formed using fine particleshaving a particle size distribution with the average particle diameterbeing 3.5 μm rather than monodisperse fine particles.

Aggregation-type Fine Particles

In a preferred embodiment of the present invention, the use ofaggregation-type fine particles among the fine particles is preferred.The aggregation-type fine particles may be identical fine particles, oralternatively may be a plurality of types of fine particles, theplurality of types being different from each other in average particlediameter. In a preferred embodiment of the present invention, theaggregation-type fine particles comprise first fine particles and secondfine particles different from the first fine particles in averageparticle diameter. Further, in a more preferred embodiment of thepresent invention, the second fine particle as such or the aggregationpart as such does not exhibit anti-dazzling properties in theanti-dazzling layer.

In the present invention, preferably, the fine particles satisfy thefollowing formula (I):

0.25R (preferably 0.50)≦r≦1.0R (preferably 0.70)  (I)

wherein R represents the average particle diameter of the fineparticles, μm; and r represents the average particle diameter of thesecond fine particles, μm.

When the r value is not less than 0.25R, the dispersion of the coatingcomposition is easy and, consequently, the particles are not aggregated.In the step of drying after coating, a uniform concavoconvex shape canbe formed without undergoing an influence of wind during floating.Further, when r is not more than 0.85R, advantageously, the function ofthe fine particles can be clearly distinguished from the function of thefirst fine particles.

In another embodiment of the present invention, preferably, the totalweight ratio per unit area among the resin, (first) fine particles, andsecond fine particles satisfies requirements represented by thefollowing formulae (II) and (III):

0.08≦(M ₁ +M ₂)/M≦0.36  (II)

0≦M₂≦4.0M₁  (III)

wherein M₁ represents the total weight of the (first) fine particles perunit area; M₂ represents the total weight of the second fine particlesper unit area; and M represents the total weight of the resin per unitarea.

In another preferred embodiment of the present invention, preferably, arequirement represented by the following formula (IV) is satisfied:

Δn=|n ₁ −n ₃|<0.15 and/or Δn=|n ₂ −n ₃|<0.18  (IV)

wherein n₁, n₂, and n₃ represent the refractive indexes of the (first)fine particles, the second fine particles, and the resin, respectively.

Fine particles (second fine particles) may be of inorganic type andorganic type and are preferably formed of an organic material. The fineparticles exhibit anti-dazzling properties and are preferablytransparent. Specific examples of such fine particles include plasticbeads, and transparent plastic beads are more preferred. Specificexamples of plastic beads include styrene beads (refractive index 1.59),melamine beads (refractive index 1.57), acrylic beads (refractive index1.49), acryl-styrene beads (refractive index 1.54), polycarbonate beads,and polyethylene beads. In a preferred embodiment of the presentinvention, the plastic bead has a hydrophobic group on its surface, and,for example, acrylic beads are preferred.

Resin

The anti-dazzling layer according to the present invention may be formedfrom a (curing-type) resin. In the present invention, the “resin” is aconcept including resin components such as monomers and oligomers. Thecuring-type resin is preferably transparent, and specific examplesthereof are classified into ionizing radiation curing resins which arecurable upon exposure to ultraviolet light or electron beams, mixturesof ionizing radiation curing resins with solvent drying resins, or heatcuring resins. Preferred are ionizing radiation curing resins.

Specific examples of ionizing radiation curing resins include thosecontaining an acrylate-type functional group, for example, oligomers orprepolymers and reactive diluents, for example, relatively low-molecularweight polyester resins, polyether resins, acrylic resins, epoxy resins,urethane resins, alkyd resins, spiroacetal resins, polybutadiene resins,and polythiol polyene resins and (meth)acrylates of polyfunctionalcompounds such as polyhydric alcohols. Specific examples thereof includemonofunctional monomers such as ethyl (meth)acrylate, ethylhexyl(meth)acrylate, styrene, methyl styrene, and N-vinylpyrrolidone, andpolyfunctional monomers, for example, polymethylolpropanetri(meth)acrylate, hexanediol (meth)acrylate, tripropylene glycoldi(meth)acrylate, diethylene glycol di(meth)acrylate, pentaerythritoltri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,6-hexanedioldi(meth)acrylate, and neopentyl glycol di(meth)acrylate.

When ionizing radiation curing resins are used as an ultraviolet curingresin, preferably, a photopolymerization initiator is used. Specificexamples of photopolymerization initiators include acetophenones,benzophenones, Michler's benzoyl benzoate, α-amyloxime ester,tetramethyl thiuram monosulfide, and thioxanthones. Preferably,photosensitizers are mixed in the system. Specific examples ofphotosensitizers include n-butylamine, triethylamine, andpoly-n-butylphosphine.

The solvent drying-type resin used as a mixture with the ionizingradiation curing resin is mainly a thermoplastic resin. Coating defectsof the coated face can be effectively prevented by adding the solventdrying-type resin. Commonly exemplified thermoplastic resins are usable.Specific examples of preferred thermoplastic resins include styrenicresins, (meth)acrylic resins, vinyl acetate resins, vinyl ether resins,halogen-containing resins, alicyclic olefinic resins, polycarbonateresins, polyester resins, polyamide resins, cellulose derivatives,silicone resins, and rubbers or elastomers. The resin is generallynoncrystalline and, at the same time, is soluble in an organic solvent(particularly a common solvent which can dissolve a plurality ofpolymers and curable compounds). Particularly preferred are resinshaving good moldability or film forming properties, transparency, andweathering resistance, for example, styrenic resins, (meth)acrylicresins, alicyclic olefinic resins, polyester resins, and cellulosederivatives (for example, cellulose esters).

In a preferred embodiment of the present invention, when the lighttransparent base material is formed of a cellulosic resin such astriacetylcellulose “TAC,” specific examples of preferred thermoplasticresins include cellulosic resins, for example, nitrocellulose,acetylcellulose, cellulose acetate propionate, andethylhydroxyethylcellulose. When the cellulosic resin is used, theadhesion between the light transparent base material and the antistaticlayer (if any) and transparency can be improved. In addition to theabove-described cellulose derivatives such as acetylcellulose,nitrocellulose, acetylbutylcellulose, ethylcellulose, andmethylcellulose, vinyl resins such as vinyl acetate and its copolymers,vinyl chloride and its copolymers, and vinylidene chloride and itscopolymers, acetal resins such as polyvinylformal and polyvinylbutyral,acrylic resins such as acrylic resin and its copolymers and methacrylicresin and its copolymers, polystyrene resins, polyamide resins, andpolycarbonate resins.

Specific examples of heat curing resin include phenolic resins, urearesins, diallyl phthalate resins, melanin resins, guanamine resins,unsaturated polyester resins, polyurethane resins, epoxy resins,aminoalkyd resins, melamine-urea cocondensed resins, silicone resins,and polysiloxane resins. When the heat curing resin is used, ifnecessary, for example, curing agents such as crosslinking agents andpolymerization initiators, polymerization accelerators, solvents, andviscosity modifiers may be further added.

Leveling Agent

In a preferred embodiment of the present invention, preferably, afluoro- or silicone-type or other leveling agent is added to thecomposition for an anti-dazzling layer. The composition for ananti-dazzling layer to which the leveling agent has been added, caneffectively prevent the inhibition of curing by oxygen to the surface ofthe coating film during coating or drying and, at the same time, impartscratch resistant effect. Preferably, the leveling agent is utilized infilm-shaped light transparent base materials (for example,triacetylcellulose) which should be resistant to heat.

2) Method for Forming Anti-dazzling Layer Using Composition forAnti-dazzling layer, Containing Resin and the Like but not ContainingFine Particles

Method for Anti-dazzling Layer Formation

The anti-dazzling layer may be formed using a composition for ananti-dazzling layer, comprising at least one polymer and at least onecurable resin precursor. The use of a composition for an anti-dazzlinglayer prepared by mixing at least one polymer and at least one curableresin precursor with a suitable solvent is advantageous in that at leastan anti-dazzling layer can be formed by forming a phase separatedstructure by spinodal decomposition from a liquid phase and curing thecurable resin precursor.

The spinodal decomposition from the liquid phase can be carried out byevaporating the solvent. The combination of materials which can form aphase separated structure may be, for example, a combination of aplurality of polymers, a combination of a polymer and a curable resinprecursor, or a combination of a plurality of curable resin precursors.In this method, an anti-dazzling layer may also be formed by subjectinga composition comprising a thermoplastic resin, a photocuring compound(for example, a photopolymerizable monomer or oligomer), aphotopolymerization initiator, and a solvent capable of dissolving thethermoplastic resin and photocurable compound (a common solvent) tospinodal decomposition to form a phase separated structure and exposingthe product to light. Alternatively, the anti-dazzling layer may beformed by subjecting a composition comprising a thermoplastic resin, aresin incompatible with the thermoplastic resin and containing aphotocurable group, a photocuring compound, a photopolymerizationinitiator, and a solvent capable of dissolving the resin and thephotocuring compound to spinodal decomposition to form a phase separatedstructure, and applying light to the assembly. In these methods, atleast one anti-dazzling layer may be formed on a light transparent basematerial.

Specific Formation Method

The anti-dazzling layer may be formed by a process comprising the stepsof: mixing at least one polymer and at least one curable resin precursorusing a proper solvent to prepare a composition for an anti-dazzlinglayer, applying the composition for an anti-dazzling layer onto a lighttransparent base material and, then subjecting the coating to spinodaldecomposition involving the evaporation of the solvent to form a phaseseparated structure; and curing the curable resin precursor to form atleast an anti-dazzling layer. The phase separation step generallycomprises the step of coating or casting a mixed liquid containing apolymer and a curable resin precursor and a solvent (particularly aliquid composition such as a homogeneous solution) onto the surface of alight transparent base material and the step of evaporating the solventfrom the coating layer or casting layer to form a phase separatedstructure having a regular or periodical average phase-to-phasedistance. The anti-dazzling layer can be formed by curing the curableresin precursor.

In a preferred embodiment of the present invention, the mixed liquid maybe a composition for an anti-dazzling layer, comprising a thermoplasticresin, a photocuring compound, a photopolymerization initiator, and asolvent capable of dissolving the thermoplastic resin and photocuringcompound. The anti-dazzling layer is formed by applying light tophotocurable components in the phase separated structure formed by thespinodal decomposition to cure the photocurable components. In anotherpreferred embodiment of the present invention, the mixed liquid may be acomposition for an anti-dazzling layer, comprising a plurality ofmutually incompatible polymers, a photocuring compound, aphotopolymerization initiator, and a solvent. In this case, theanti-dazzling layer is formed by applying light to photocurablecomponents in the phase separated structure formed by the spinodaldecomposition to cure the photocurable components.

The spinodal decomposition involving the evaporation of the solvent canimpart regularity or periodicity to the average distance between domainsin the phase separated structure. The phase separated structure formedby the spinodal decomposition can be immediately fixed by curing thecurable resin precursor. The curable resin pecursor can be cured, forexample, by heating or light irradiation or a combination of thesemethods according to the type of the curable resin precursor. Theheating temperature can be selected, for example, from a suitabletemperature range, for example, from a range of approximately 50 to 150°C., so far as the phase separated structure is present, and may beselected from the same temperature range as in the phase separationstep.

The anti-dazzling layer constituting a part of the optical laminate isformed by forming a phase separated structure in the anti-dazzling layerby spinodal decomposition (wet spinodal decomposition) from a liquidphase. Specifically, a composition for an anti-dazzling layer accordingto the present invention, comprising a polymer, a curable resinprecursor, and a solvent is provided. The solvent is evaporated orremoved from the composition for an anti-dazzling layer in its liquidphase (or a homogeneous solution or coating layer thereof) by drying orthe like. In the course of drying or the like, an increase inconcentration causes phase separation by spinodal decomposition to forma phase separated structure having a relatively regular phase-to-phasedistance. More specifically, the wet spinodal decomposition is generallycarried out by coating a composition for an anti-dazzling layer(preferably a homogeneous solution) comprising at least one polymer, atleast one curable resin precursor, and a solvent onto a support andevaporating the solvent from the coating layer.

In the present invention, in the spinodal decomposition, as the phaseseparation proceeds, a co-continuous phase structure is formed. As thephase separation further proceeds, the continuous phase is rendereddiscontinuous by the surface tension of the phase per se to form aliquid droplet phase structure (a sea-island structure of spherical,truly spherical, disk-like, elliptical or other independent phases).Accordingly, depending upon the degree of the phase separation, astructure intermediate between a co-continuous structure and a liquiddroplet phase structure (a phase structure in the course of transferfrom the co-continuous phase to the liquid droplet phase) can also beformed. The phase separated structure of the anti-dazzling layeraccording to the present invention may be a sea-island structure (aliquid droplet phase structure or a phase structure in which one of thephases is independent or isolated), a co-continuous phase structure (ora network structure), or an intermediate structure in which aco-continuous phase structure and a liquid droplet phase structure existtogether. By virtue of the phase separated structure, after the removalof the solvent by drying, fine concavoconvexes can be formed on thesurface of the anti-dazzling layer.

In the phase separated structure, concavoconvexes are formed on thesurface of the anti-dazzling layer, and, from the viewpoint of enhancingthe surface hardness, a liquid droplet phase structure having at leastisland domains is advantageous. When the phase separated structurecomposed of the polymer and the precursor (or curable resin) is asea-island structure, the polymer component may constitutes a sea phase.From the viewpoint of the surface hardness, however, the polymercomponent preferably constitutes island domains. The formation of islanddomains leads to the formation of a concavoconvex shape having desiredoptical characteristics on the surface of the anti-dazzling layer afterdrying.

The average distance between domains in the phase separated structure isgenerally substantially regular or periodical. For example, the averagephase-to-phase distance of domains may be, for example, approximately 1to 70 μm (for example, 1 to 40 μm), preferably 2 to 50 μm (for example,3 to 30 μm), more preferably 5 to 20 μm (for example, 10 to 20 μm).

Polymer

The polymer may be a plurality of polymers which can be phase separatedby a spinodal decomposition, for example, a cellulose derivative and astyrenic resin, an (meth)acrylic resin, an alicyclic olefinic resin, apolycarbonate resin, a polyester resin or the like, or a combinationthereof. The curable resin precursor may be compatible with at least onepolymer in the plurality of polymers. At least one of the plurality ofpolymers may have a functional group involved in a curing reaction ofthe curable resin precursor, for example, a polymerizable group such asan (meth)acryloyl group. In general, a thermoplastic resin is used asthe polymer component.

Specific examples of thermoplastic resins include styrenic resins,(meth)acrylic resins, organic acid vinyl ester resins, vinyl etherresins, halogen-containing resins, olefinic resins (including alicyclicolefinic resins), polycarbonate resins, polyester resins, polyamideresins, thermoplastic polyurethane resins, polysulfone resins (forexample, polyethersulfone and polysulfone), polyphenylene ether resins(for example, polymers of 2,6-xylenol), cellulose derivatives (forexample, cellulose esters, cellulose carbamates, and cellulose ethers),silicone resins (for example, polydimethylsiloxane andpolymethylphenylsiloxane), and rubbers or elastomers (for example, dienerubbers such as polybutadiene and polyisoprene, styrene-butadienecopolymers, acrylonitrile-butadiene copolymers, acrylic rubbers,urethane rubbers, and silicone rubbers). They may be used either solelyor in a combination of two or more.

Specific examples of styrenic resins include homopolymers or copolymersof styrenic monomers (for example, polystyrenes, styrene-α-methylstyrenecopolymers, and styrene-vinyltoluene copolymers) and copolymers ofstyrenic monomers with other polymerizable monomers (for example,(meth)acrylic monomers, maleic anhydride, maleimide monomers, ordienes). Styrenic copolymers include, for example, styrene-acrylonitrilecopolymers (AS resins), copolymers of styrene with (meth)acrylicmonomers (for example, styrene-methyl methacrylate copolymers,styrene-methyl methacrylate-(meth)acrylic ester copolymers, orstyrene-methyl methacrylate-(meth)acrylic acid copolymers), andstyrene-maleic anhydride copolymers. Preferred styrenic resins includecopolymers of polystyrene or styrene with (meth)acrylic monomers (forexample, copolymers composed mainly of styrene and methyl methacrylate,for example, styrene-methyl methacrylate copolymers), AS resins, andstyrene-butadiene copolymers.

For example, homopolymers or copolymers of (meth)acrylic monomers andcopolymers of (meth)acrylic monomers with copolymerizable monomers maybe mentioned as the (meth)acrylic resin. Specific examples of(meth)acrylic monomers include (meth)acrylic acid; C₁₋₁₀ alkyl(meth)acrylates such as methyl (meth)acrylate, ethyl (meth)acrylate,butyl (meth)acrylate, t-butyl (meth)acrylate, isobutyl (meth)acrylate,hexyl (meth)acrylate, octyl (meth)acrylate, and 2-ethylhexyl(meth)acrylate; aryl (meth)acrylates such as phenyl (meth)acrylate;hydroxyalkyl (meth)acrylate such as hydroxyethyl (meth)acrylate andhydroxypropyl (meth)acrylate; glycidyl (meth)acrylate;N,N-dialkylaminoalkyl (meth)acrylate; (meth)acrylonitrile; and(meth)acrylates containing an alicyclic hydrocarbon group, such astricyclodecane. Specific examples of copolymerizable monomers includethe above styrenic monomers, vinyl ester monomers, maleic anhydride,maleic acid, and fumaric acid. These monomers may be used either solelyor in a combination of two or more.

Specific examples of (meth)acrylic resins include poly(meth)acrylicesters such as polymethyl methacrylate, methylmethacrylate-(meth)acrylic acid copolymers, methylmethacrylate-(meth)acrylic ester copolymers, methyl methacrylate-acrylicester-(meth)acrylic acid copolymers, and (meth)acrylic ester-styrenecopolymers (for example, MS resins). Specific examples of preferred(meth)acrylic resins include poly-C₁₋₆ alkyl (meth)acrylates such aspolymethyl (meth)acrylate. In particular, methyl methacrylate resinscomposed mainly of methyl methacrylate (approximately 50 to 100% byweight, preferably 70 to 100% by weight) may be mentioned.

Specific examples of organic acid vinyl ester resins includehomopolymers or copolymers of vinyl ester monomers (for example,polyvinyl acetate and polyvinyl propionate), copolymers of vinyl estermonomers with copolymerizable monomers (for example, ethylene-vinylacetate copolymers, vinyl acetate-vinyl chloride copolymers, and vinylacetate-(meth)acrylic ester copolymers), or their derivatives. Specificexamples of vinyl ester resin derivatives include polyvinyl alcohol,ethylene-vinyl alcohol copolymers, and polyvinylacetal resins.

Specific examples of vinyl ether resins include homopolymers orcopolymers of vinyl C₁₋₁₀ alkyl ethers such as vinyl methyl ether, vinylethyl ether, vinyl propyl ether, or vinyl t-butyl ether, copolymers ofvinyl C₁₋₁₀ alkyl ethers with copolymerizable monomers (for example,vinyl alkyl ether-maleic anhydride copolymers). Specific examples ofhalogen-containing resins include polyvinyl chloride, polyfulorinatedvinylidenes, vinyl chloride-vinyl acetate copolymers, vinylchloride-(meth)acrylic ester copolymers, and vinylidenechloride-(meth)acrylic ester copolymers.

Specific examples of olefinic resins include homopolymers of olefinssuch as polyethylene and polypropylene, and copolymers such asethylene-vinyl acetate copolymers, ethylene-vinyl alcohol copolymers,ethylene-(meth)acrylic acid copolymers, and ethylene-(meth)acrylic estercopolymers. Specific examples of alicyclic olefinic resins includehomopolymers or copolymers of cyclic olefins (for example, norbornene,dicyclopentadiene) (for example, polymers containing an alicyclichydrocarbon group such as tricyclodecane which is sterically rigid), andcopolymers of the above cyclic olefins with copolymerizable monomers(for example, ethylene-norbornene copolymers and propylene-norbornenecopolymers). Specific examples of alicyclic olefinic resins includethose which are available, for example, under the tradenames “ARTON” and“ZEONEX.”

Specific examples of polycarbonate resins include aromaticpolycarbonates based on bisphenols (for example, bisphenol A), andaliphatic polycarbonates such as diethylene glycol bisallyl carbonates.

Specific examples of polyester resins include aromatic polyesters usingaromatic dicarboxylic acids such as terephthalic acid, for example,homopolyesters, for example, poly-C₂₋₄-alkylene terephthalates andpoly-C₂₋₄-alkylene naphthalates including polyethylene terephthalate andpolybutylene terephthalate, and copolyesters comprising as a maincomponent (for example, not less than 50% by weight) C₂₋₄ alkylenearylate units (C₂₋₄ alkylene terephthalate and/or C₂₋₄ alkylenenaphthalate units). Specific examples of copolyesters includecopolyesters in which, in the constituent units of poly-C₂₋₄-alkylenearylate, a part of C₂₋₄ alkylene glycol has been replaced, for example,with a polyoxy-C₂₋₄-alkylene glycol, a C₆₋₁₀ alkylene glycol, analicyclic diol (for example, cyclohexanedimethanol or hydrogenatedbisphenol A), an aromatic ring-containing diol (for example,9,9-bis(4-(2-hydroxyethoxy)phenyl)fluorene having a fluorenone sidechain, bisphenol A, or a bisphenol A-alkylene oxide adduct), andcopolyesters in which a part of aromatic dicarboxylic acid has beenreplaced, for example, with an aliphatic C₆₋₁₂ dicarboxylic acid, forexample, an asymmetric aromatic dicarboxylic acid such as phthalic acidor isophthalic acid, or adipic acid. Specific examples of polyesterresins include polyarylate resins, aliphatic polyesters using aliphaticdicarboxylic acids such as adipic acid, and homopolymers and copolymersof lactones such as c-caprolactone. Preferred polyester resins aregenerally noncrystalline polyester resins such as noncrystallinecopolyesters (for example, C₂₋₄ alkylene arylate copolyesters).

Specific examples of polyamide resins include aliphatic polyamides suchas nylon 46, nylon 6, nylon 66, nylon 610, nylon 612, nylon 11, andnylon 12, and polyamides produced from dicarboxylic acids (for example,terephthalic acid, isophthalic acid, or adipic acid) and diamines (forexample, hexamethylenediamine or metaxylylenediamine). Specific examplesof polyamide resins include homopolymers or copolymers of lactams suchas ε-caprolactam. The polyamide resins may be either homopolyamides orcopolyamides.

Specific examples of cellulose esters among the cellulose derivativesinclude, for example, aliphatic organic acid esters, for example,cellulose acetates such as cellulose diacetate and cellulose triacetate;and C₁₋₆ organic acid esters such as cellulose propionate, cellulosebutyrate, cellulose acetate propionate, and cellulose acetate butyrate.Further examples thereof include aromatic organic acid esters (C₇₋₁₂aromatic carboxylic esters such as cellulose phthalate and cellulosebenzoate) and inorganic acid esters, for example, cellulose phosphateand cellulose sulphate. Mixed acid esters such as acetic acid-nitricacid cellulose ester may also be used. Specific examples of cellulosederivatives include cellulose carbamates (for example, cellulosephenylcarbamate) and further include cellulose ethers, for example,cyanoethylcellulose; hydroxy-C₂₋₄-alkylcelluloses such ashydroxyethylcellulose and hydroxypropylcellulose; C₁₋₆ alkylcellulosessuch as methylcellulose and ethylcellulose; and carboxymethylcelluloseor its salt, benzylcellulose, and acetylalkylcellulose.

Specific examples of preferred thermoplastic resins include styrenicresins, (meth)acrylic resins, vinyl acetate resins, vinyl ether resins,halogen-containing resins, alicyclic olefinic resins, polycarbonateresins, polyester resins, polyamide resins, cellulose derivatives,silicone resins, rubbers or elastomers. Resins, which are usuallynoncrystalline and soluble in organic solvents (particularly commonsolvents which can dissolve a plurality of polymers or curablecompounds). Particularly preferred are, for example, resins having ahigh level of moldability or film formability, transparency andweathering resistance, for example, styrenic resins, (meth)acrylicresins, alicyclic olefinic resins, polyester resins, and cellulosederivatives (for example, cellulose esters).

Polymers containing a functional group involved in a curing reaction (ora functional group reactive with a curable compound) are also usable asthe polymer component. The polymers may contain a functional group inthe main chain or side chain. The functional group may be introducedinto the main chain, for example, by copolymerization orco-condensation. In general, however, the functional group is introducedinto the side chain. Specific examples of such functional groups includecondensable groups and reactive groups (for example, hydroxyl group,acid anhydride group, carboxyl group, amino group or imino group, epoxygroup, glycidyl group, and isocyanate group), polymerizable groups (forexample, C₂₋₆ alkenyl groups such as vinyl, propenyl, isopropenyl,butenyl and allyl groups, C₂₋₆ alkynyl groups such as ethynyl, propynyl,and butynyl groups, and C₂₋₆ alkenylidene groups such as vinylidene), orgroups containing these polymerizable groups (for example,(meth)acryloyl group). Among these functional groups, polymerizablegroups are preferred.

The polymerizable group may be introduced into the side chain, forexample, by reacting a thermoplastic resin containing a functional groupsuch as a reactive group or a condensable group with a polymerizablecompound containing a group reactive with the functional group.

Examples of such functional group-containing thermoplastic resinsinclude thermoplastic resins containing a carboxyl group or its acidanhydride group (for example, (meth)acrylic resins, polyester resins,and polyamide resins), hydroxyl group-containing thermoplastic resins(for example, (meth)acrylic resins, polyurethane resins, cellulosederivatives, and polyamide resins), amino group-containing thermoplasticresins (for example, polyamide resins), epoxy group-containingthermoplastic resins (for example, epoxy group-containing (meth)acrylicresins and polyester resins). Resins comprising the above functionalgroup introduced into thermoplastic resins such as styrenic resins,olefinic resins, or alicyclic olefinic resins by copolymerization orgraft polymerization are also possible.

Regarding the polymerizable compound, thermoplastic resins containing acarboxyl or its acid anhydride group include polymerizable compoundscontaining epoxy, hydroxyl, amino, or isocyanate groups. Hydroxylgroup-containing thermoplastic resins include polymerizable compoundscontaining carboxyl groups or acid anhydride groups thereof orisocyanate groups. Amino group-containing thermoplastic resins includepolymerizable compounds containing carboxyl groups or acid anhydridegroups thereof, epoxy groups, and isocyanate groups. Epoxygroup-containing thermoplastic resins include polymerizable compoundscontaining carboxyl groups or acid anhydride groups thereof or aminogroups.

Among the above polymerizable compounds, epoxy group-containingpolymerizable compounds include, for example, epoxycyclo-C₅₋₈-alkenyl(meth)acrylates such as epoxycyclohexenyl (meth)acrylate, glycidyl(meth)acrylate, and allyl glycidyl ether. Hydroxyl group-containingcompounds include, for example, hydroxy-C₁₋₄-alkyl (meth)acrylates suchas hydroxypropyl (meth)acrylate, and C₂₋₆ alkylene glycol(meth)acrylates such as ethylene glycol mono(meth)acrylate. Aminogroup-containing polymerizable compounds include, for example,amino-C₁₋₄-alkyl (meth)acrylates such as aminoethyl (meth)acrylate, C₃₋₆alkenylamines such as allylamine, and aminostyrenes such as4-aminostyrene and diaminostyrene. Isocyanate group-containingpolymerizable compounds include, for example, (poly)urethane(meth)acrylate and vinyl isocyanate. Polymerizable compounds containingcarboxyl groups or acid anhydride groups thereof include, for example,unsaturated carboxylic acids or anhydrides thereof such as (meth)acrylicacid and maleic anhydride.

A combination of a thermoplastic resin containing a carboxyl group orits acid anhydride group with an epoxy group-containing compound,particularly a combination of an (meth)acrylic resin (for example, an(meth)acrylic acid-(meth)acrylic ester copolymer) with an epoxygroup-containing (meth)acrylate (for example, epoxycycloalkenyl(meth)acrylate or glycidyl (meth)acrylate) may be mantioned as arepresentative example of the polymerizable compound. Specific examplesthereof include polymers comprising a polymerizable unsaturated groupintroduced into a part of carboxyl groups in an (meth)acrylic resin, forexample, an (meth)acrylic polymer produced by reacting a part ofcarboxyl groups in an (meth)acrylic acid-(meth)acrylic ester copolymerwith an epoxy group in 3,4-epoxycyclohexenylmethyl acrylate to introducea photopolymerizable unsaturated group into the side chain (CYCLOMER P,manufactured by Daicel Chemical Industries, Ltd.).

The amount of the functional group (particularly polymerizable group)involved in a curing reaction with the thermoplastic resin introduced isapproximately 0.001 to 10 moles, preferably 0.01 to 5 moles, morepreferably 0.02 to 3 moles based on 1 kg of the thermoplastic resin.

These polymers may be used in a suitable combination. Specifically, thepolymer may comprise a plurality of polymers. The plurality of polymersmay be phase separated by liquid phase spinodal decomposition. Theplurality of polymers may be incompatible with each other. When theplurality of polymers are used in combination, the combination of afirst resin with a second resin is not particularly limited. Forexample, a plurality of suitable polymers incompatible with each otherat a temperature around a processing temperature, for example, twosuitable polymers incompatible with each other may be used. For example,when the first resin is a styrenic resin (for example, polystyrene or astyrene-acrylonitrile copolymer), examples of second resins usableherein include cellulose derivatives (for example, cellulose esters suchas cellulose acetate propionate), (meth)acrylic resins (for example,polymethyl methacrylate), alicyclic olefinic resins (for example,polymers using norbornene as a monomer), polycarbonate resins, andpolyester resins (for example, the above poly-C₂₋₄-alkylene arylatecopolyesters). On the other hand, for example, when the first polymer isa cellulose derivative (for example, a cellulose ester such as celluloseacetate propionate), examples of second polymers usable herein includestyrenic resins (for example, polystyrene or styrene-acrylonitrilecopolymer), (meth)acrylic resins, alicyclic olefinic resins (forexample, polymers using norbornene as a monomer), polycarbonate resins,and polyester resins (for example, the above poly-C₂₋₄-alkylene arylatecopolyester). In the combination of the plurality of resins, at leastcellulose esters (for example, cellulose C₂₋₄ alkyl carboxylic esterssuch as cellulose diacetate, cellulose triacetate, cellulose acetatepropionate, or cellulose acetate butyrate) may be used.

The phase separated structure produced by the spinodal decomposition isfinally cured by the application of an actinic radiation (for example,ultraviolet light or electron beam), heat or the like to form a curedresin. By virtue of this, the scratch resistance can be imparted to theanti-dazzling layer, and the durability can be improved.

From the viewpoint of scratch resistance after curing, preferably, atleast one polymer in the plurality of polymers, for example, one ofmutually incompatible polymers (when the first and second resins areused in combination, particularly both the polymers) is a polymer havingon its side chain a functional group reactive with a curable resinprecursor.

The weight ratio between the first polymer and the second polymer may beselected, for example, from a range of first polymer/secondpolymer=approximately 1/99 to 99/1, preferably 5/95 to 95/5, morepreferably 10/90 to 90/10 and is generally approximately 20/80 to 80/20,particularly 30/70 to 70/30.

Regarding the polymer for phase separated structure formation, inaddition to the above two incompatible polymers, the above thermoplasticresins or other polymers may be incorporated.

The glass transition temperature of the polymer may be selected, forexample, from a range of approximately −100° C. to 250° C., preferably−50° C. to 230° C., more preferably 0 to 200° C. (for example,approximately 50 to 180° C.). A glass transition temperature of 50° C.or above (for example, approximately 70 to 200° C.), preferably 100° C.or above (for example, approximately 100 to 170° C.), is advantageousfrom the viewpoint of the surface hardness. The weight average molecularweight of the polymer may be selected, for example, from a range ofapproximately not more than 1,000,000, preferably 1,000 to 500,000.

Curable Resin Precursor

The curable resin precursor is a compound containing a functional groupwhich can be reacted upon exposure, for example, to heat or an actinicradiation (for example, ultraviolet light or electron beams), andvarious curable compounds, which can be cured or crosslinked uponexposure to heat, an actinic radiation or the like to form a resin(particularly a cured or crosslinked resin), can be used. Examples ofsuch resin precursors include heat curing compounds or resins[low-molecular weight compounds containing epoxy groups, polymerizablegroups, isocyanate groups, alkoxysilyl groups, or silanol groups (forexample, epoxy resins, unsaturated polyester resins, urethane resins, orsilicone resins)], and photocuring compounds curable upon exposure to anactinic radiation (for example, ultraviolet light) (for example,ultraviolet light curing compounds such as photocuring monomers andoligomers). The photocuring compound may be, for example, an EB(electron beam) curing compound. Photocuring compounds such asphotocuring monomers, oligomers, photocuring resins which may have alow-molecular weight, are sometimes referred to simply as “photocuringresin.”

Photocuring compounds include, for example, monomers and oligomers (orresins, particularly low-molecular weight resins). Monomers include, forexample, monofunctional monomers [(meth)acrylic monomers such as(meth)acrylic esters, vinyl monomers such as vinylpyrrolidone,crosslinked ring-type hydrocarbon group-containing (meth)acrylates suchas isobornyl (meth)acrylate or adamantyl (meth)acrylate)],polyfunctional monomers containing at least two polymerizableunsaturated bonds [for example, alkylene glycol di(meth)acrylates suchas ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate,butanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, andhexanediol di(meth)acrylate; (poly)oxyalkylene glycol di(meth)acrylatessuch as diethylene glycol di(meth)acrylate, dipropylene glycoldi(meth)acrylate, and polyoxytetramethylene glycol di(meth)acrylate;crosslinked ring-type hydrocarbon group-containing di(meth)acrylatessuch as tricyclodecane dimethanol di(meth)acrylate and adamantanedi(meth)acrylate; and polyfunctional monomers containing about three tosix polymerizable unsaturated bonds such as trimethylolpropanetri(meth)acrylate, trimethylolethane tri(meth)acrylate, pentaerythritoltri(meth)acrylate, pentaerythritol tetra(meth)acrylate, anddipentaerythritol penta(meth)acrylate].

Oligomers or resins include (meth)acrylate or epoxy (meth)acrylate ofbisphenol A-alkylene oxide adducts (for example, bisphenol A-type epoxy(meth)acrylate and novolak-type epoxy (meth)acrylate), polyester(meth)acrylates (for example, aliphatic polyester-type (meth)acrylateand aromatic polyester-type (meth)acrylate), (poly)urethane(meth)acrylate (for example, polyester-type urethane (meth)acrylate,polyether-type urethane (meth)acrylate), and silicone (meth)acrylate.These photocuring compounds are usable either solely or in a combinationof two or more.

Preferred curable resin precursors include photocuring compounds curablein a short time, for example, ultraviolet light curing compounds (forexample, monomers, oligomers and resins which may have a low-molecularweight), and EB curing compounds. Resin precursors which areparticularly advantageous from the practical viewpoint are ultravioletcuring resins. From the viewpoint of improving resistance such asscratch resistance, preferably, the photocuring resin is a compoundhaving in its molecule two or more (preferably approximately 2 to 6,more preferably 2 to 4) polymerizable unsaturated bonds. The molecularweight of the curable resin precursor is approximately not more than5000, preferably not more than 2000, more preferably not more than 1000,from the viewpoint of compatibility with the polymer.

The curable resin precursor may contain a curing agent depending uponthe type of the curable resin pecursor. For example, in the case of heatcuring resins, curing agents such as amines or polycarboxylic acids maybe contained, and, in the case of photocuring resins,photopolymerization initiators may be contained. Examples ofphotopolymerization initiators include commonly used components, forexample, acetophenones or propiophenones, benzyls, benzoins,benzophenones, thioxanthones, and acylphosphine oxides. The content ofthe curing agent such as a photocuring agent is approximately 0.1 to 20parts by weight, preferably 0.5 to 10 parts by weight, more preferably 1to 8 parts by weight (particularly 1 to 5 parts by weight), based on 100parts by weight of the curable resin precursor and may be approximately3 to 8 parts by weight.

The curable resin precursor may contain a curing accelerator. Forexample, the photocuring resin may contain photocuring accelerators, forexample, tertiary amines (for example, dialkylaminobenzoic esters) andphosphine photopolymerization accelerators.

Specific Combination of Polymer with Curable Resin Precursor

At least two components in at least one polymer and at least one curableresin percursor may be used in a combination of materials which aremutually phase separated at a temperature around the processingtemperature. Examples of such combinations include (a) a combination ofa plurality of polymers which are mutually incompatible and phaseseparated, (b) a combination of a polymer and a curable resin precursorwhich are mutually incompatible and phase separated, and (c) acombination of a plurality of curable resin precursors which aremutually incompatible and phase separated. Among these combinations, (a)a combination of a plurality of polymers and (b) a combination of apolymer with a curable resin precursor are generally preferred, andparticulary (a) a combination of a plurality of polymers is preferred.When the compatibility of both the materials to be phase separated islow, both the materials are effectively phase separated in the course ofdrying for evaporating the solvent and the function as an anti-dazzlinglayer can be improved.

The thermoplastic resin and the curable resin precursor (or curing-typeresin) are generally incompatible with each other. When the polymer andthe curable resin precursor are incompatible with each other and phaseseparated, a plurality of polymers may be used as the polymer. When aplurality of polymers are used, meeting the requirement that at leastone polymer is incompatible with the resin precursor (or curing-typeresin) suffices for contemplated results, and the other polymer(s) maybe compatible with the resin precursor.

A combination of two mutually incompatible thermoplastic resins with acuring compound (particularly a monomer or oligomer containing aplurality of curable functional groups) may be adopted. From theviewpoint of scratch resistance after curing, one polymer (particularlyboth polymers) in the incompatible thermoplastic resins may be athermoplastic resin containing a functional group involved in the curingreaction (a functional group involved in curing of the curable resinprecursor).

When a combination of a plurality of mutually incompatible polymers isadopted for phase separation, the curable resin precursor to be used incombination with the plurality of mutually incompatible polymers iscompatible with at least one polymer in the plurality of incompatiblepolymers at a temperature around the processing temperature.Specifically, for example, when the plurality of mutually incompatiblepolymers are constituted by the first resin and the second resin, thecurable resin precursor may be one which is compatible with at least oneof the first resin and the second resin, preferably is compatible withboth the polymer components. When the curable resin precursor iscompatible with both the polymer components, phase separation occursinto at least two phases, i.e., a mixture composed mainly of a firstresin and a curable resin precursor and a mixture composed mainly of asecond resin and a curable resin precursor.

When the compatibility of a plurality of selected polymers is low, thepolymers are effectively phase separated from each other in the courseof drying for evaporating the solvent and the function as ananti-dazzling layer is improved. The phase separability of the pluralityof polymers can be simply determined by a method in which a homogeneoussolution is prepared using a good solvent for both the components andthe solvent is gradually evaporated to visually inspect whether or notthe residual solid matter is opaque in the course of drying.

In general, the polymer and the cured or crosslinked resin produced bycuring of the resin precursor are different from each other inrefractive index. Further, the plurality of polymers (first and secondresins) are also different from each other in refractive index. Thedifference in refractive index between the polymer and the cured orcrosslinked resin, and the difference in refractive index between theplurality of polymers (first and second resins) may be, for example,approximately 0.001 to 0.2, preferably 0.05 to 0.15.

The weight ratio between the polymer and the curable resin precursor isnot particularly limited and may be selected, for example, from a rangeof polymer/curable resin precursor=approximately 5/95 to 95/5, and, fromthe viewpoint of surface hardness, is preferably polymer/curable resinprecursor=approximately 5/95 to 60/40, more preferably 10/90 to 50/50,particularly preferably 10/90 to 40/60.

Solvent

The solvent may be selected and used according to the type andsolubility of the polymer and curable resin precursor. A solvent capableof homogeneously dissolving at least the solid matter (a plurality ofpolymers and curable resin precursor, a reaction initiator, and otheradditives) suffices for contemplated results and may be used in wetspinodal decomposition. Examples of such solvents include ketones (forexample, acetone, methyl ethyl ketone, methyl isobutyl ketone, andcyclohexanone), ethers (for example, dioxane and tetrahydrofuran),aliphatic hydrocarbons (for example, hexane), alicyclic hydrocarbons(for example, cyclohexane), aromatic hydrocarbons (for example, tolueneand xylene), halogenated hydrocarbons (for example, dichloromethane anddichloroethane), esters (for example, methyl acetate, ethyl acetate andbutyl acetate), water, alcohols (for example, ethanol, isopropanol,butanol, and cyclohexanol), cellosolves (for example, methylcellosolveand ethylcellosolve), cellosolve acetates, sulfoxides (for example,dimethylsulfoxide), and amides (for example, dimethylformamide anddimethylacetamide). A mixture solvents composed of two or more of thesesolvents may be used.

The concentration of the solute (polymer and curable resin precursor,reaction initiator, and other additives) in the composition for ananti-dazzling layer may be selected from such a range that causes phaseseparation and such a range that castability, coatability and the likeare not deteriorated. The solute concentration is, for example,approximately 1 to 80% by weight, preferably 5 to 60% by weight, morepreferably 15 to 40% by weight (particularly 20 to 40% by weight).

3) Method for Forming Anti-dazzling Layer Using Treatment for Impartinga Concavoconvex Shape

The anti-dazzling layer according to the present invention may be formedby subjecting the surface of an anti-dazzling layer, formed using a fineparticle-free composition for an anti-dazzling layer comprising apolymer, a resin and the like or an anti-dazzling layer, which is notyet in a completed state, that is, during a stage of formation, totreatment for imparting a concavoconvex shape. This method may be thesame as described above in connection with the production process andproduction apparatus according to the present invention.

2. Surface Modifying Layer

In the present invention, a surface modifying layer may be formed toregulate the concavoconvex surface of the anti-dazzling layer. In thiscase, the surface modifying layer is integrated with the anti-dazzlinglayer to exhibit an anti-dazzling function. Accordingly, in theformation of the surface modifying layer, optical property values suchas Sm, θa, and Rz as surface concavoconvex shape values fall within thescope of the present invention. Further, when the surface modifyinglayer is applied onto the anti-dazzling layer, the surface concavoconvexshape of the surface modifying layer is of course identical to theoptical property values of the surface concavoconvex shape of theanti-dazzling layer in the present invention. The above matter can beunderstood from the following detailed description on the surfacemodifying layer and working examples.

In the surface modifying layer, fine concavoconvexes present along theconcavoconvex shape on the scale of one-tenth or less of theconcavo-convex scale (profile peak height of concavoconvexes and spacingbetween profile peaks) in the surface roughness constituting theconcavoconvex shape of the anti-dazzling layer can be sealed forsmoothing to form smooth concavoconvexes, or the spacing between profilepeaks of the concavoconvexes and peak profile height, and the frequency(number) of the profile peaks can be regulated. The surface modifyinglayer can be formed, for example, for imparting antistatic properties,refractive index regulation, hardness enhancement, contaminationpreventive properties and the like. The thickness (on a cured statebases) of the surface modifying layer is not less than 0.5 μm and notmore than 27 μm (preferably not more than 12 μm). Preferably, the lowerlimit of the thickness of the surface modifying layer is 3 μm, and theupper limit of the thickness of the surface modifying layer is 8 μm.

Surface Modifying Agent

One material or a mixture of two or more materials selected from thegroup consisting of antistatic agents, refractive index regulatingagents, contamination preventive agents, water repellants, oilrepellents, fingerprint adhesion preventive agents, curability enhancingagents, and hardness regulating agents (cushioning property impartingagents) may be mentioned as the surface modifying agent.

Antistatic Agent (Electroconductive Agent)

When an antistatic agent is contained in the surface modifying layer,dust adhesion to the surface of the optical laminate can, be effectivelyprevented. Specific examples of antistatic agents include cationicgroup-containing various cationic compounds such as quaternary ammoniumsalts, pyridinium salts, primary, secondary and tertiary amino groups,anionic group-containing anionic compounds such as sulfonic acid bases,sulfuric ester bases, phosphoric ester bases, and phosphonic acid bases,amphoteric compounds such as amino acid and aminosulfuric estercompounds, nonionic compounds such as amino alcohol, glycerin andpolyethylene glycol compounds, organometallic compounds such asalkoxides of tin and titanium, and metal chelate compounds such as theiracetylacetonate salts. Further, compounds produced by increasing themolecular weight of the above compounds may also be mentioned. Further,poloymerizable compounds, for example, monomers or oligomers, whichcontain a tertiary amino group, a quaternary ammonium group, or ametallic chelate moiety and are polymerizable upon exposure to ionizingradiations, or organometallic compounds such as functionalgroup-containing coupling agents may also be used as the antistaticagent.

Further, electroconductive ultrafine particles may be mentioned as theantistatic agent. Specific examples of electroconductive ultrafineparticles include ultrafine particles of metal oxides. Such metal oxidesinclude ZnO (refractive index 1.90; the numerical values within theparentheses being refractive index; the same shall apply hereinafter),CeO₂ (1.95), Sb₂O₂ (1.71), SnO₂ (1.997), indium tin oxide oftenabbreviated to “ITO” (1.95), In₂O₃ (2.00), Al₂O₃ (1.63), antimony-dopedtin oxide (abbreviated to “ATO,” 2.0), and aluminum-doped zinc oxide(abbreviated to “AZO,” 2.0). The term “fine particles” refers to fineparticles having a size of not more than 1 micrometer, that is, fineparticles of submicron size, preferably fine particles having an averageparticle diameter of 0.1 nm to 0.1 μm.

In a preferred embodiment of the present invention, the addition amountratio of the resin to the antistatic agent contained in the surfacemodifying layer is not less than 5 and not more than 25. Preferably, theupper limit of the addition amount ratio is 20, and the lower limit ofthe addition amount ratio is 5.

Electroconductive polymers may be mentioned as the antistatic agent, andspecific examples thereof include aliphatic conjugated polyacetylenes,aromatic conjugated poly(paraphenylenes), heterocyclic conjugatedpolypyrroles, polythiophenes, heteroatom-containing conjugatedpolyanilines, and mixture-type conjugated poly(phenylenevinylenes).Additional examples of electroconductive polymers include double-chainconjugated systems which are conjugated systems having a plurality ofconjugated chains in the molecule thereof, and electroconductivecomposites which are polymers prepared by grafting orblock-copolymerizing the above conjugated polymer chain onto a saturatedpolymer.

Refractive Index Regulating Agent

The refractive index regulating agent may be added to the surfacemodifying layer to regulate the optical properties of the opticallaminate. Examples of such refractive index regulating agents includelow-refractive index agents, medium-refractive index agents, andhigh-refractive index agents.

1) Low-refractive Index Agent

The low-refractive index agent has a lower refractive index than theanti-dazzling layer. In a preferred embodiment of the present invention,the anti-dazzling layer has a refractive index of not less than 1.5, andthe low-refractive index agent has a refractive index of less than 1.5,preferably not more than 1.45.

Specific examples of low-refractive index agents includesilicone-containing vinylidene fluoride copolymers, and an examplethereof is a composition comprising 100 parts by weight of afluorine-containing copolymer and 80 to 150 parts by weight of anethylenically unsaturated group-containing polymerizable compound. Thefluorine-containing copolymer has a fluorine content of 60 to 70% byweight and is produced by copolymerizing a monomer compositioncomprising 30 to 90% by weight of vinylidene fluoride and 5 to 50% byweight of hexafluoropropylene.

A copolymer produced by copolymerizing a monomer composition containingvinylidene fluoride and hexafluoropropylene may be mentioned as thefluorine-containing copolymer. Regarding the proportion of eachcomponent in the monomer composition, the content of vinylidene fluorideis 30 to 90% by weight, preferably 40 to 80% by weight, particularlypreferably 40 to 70% by weight, or the content of hexafluoropropylene is5 to 50% by weight, preferably 10 to 50% by weight, particularlypreferably 15 to 45% by weight. The monomer composition may furthercomprise 0 to 40% by weight, preferably 0 to 35% by weight, particularlypreferably 10 to 30% by weight, of tetrafluoroethylene.

The monomer composition for producing the fluorine-containing copolymermay if necessary contain other comonomer component(s), for example, inan amount of not more than 20% by weight, preferably not more than 10%by weight. Specific examples of such comonomer components includefluorine atom-containing polymerizable monomers such as fluoroethylene,trifluoroethylene, chlorotrifluoroethylene,1,2-dichloro-1,2-difluoroethylene, 2-bromo-3,3,3-trifluoroethylene,3-bromo-3,3-difluoropropylene, 3,3,3-trifluoropropylene,1,1,2-trichloro-3,3,3-trifluoropropylene, and α-trifluoromethacrylicacid.

The content of fluorine in the fluorine-containing copolymer producedfrom the monomer composition is preferably 60 to 70% by weight, morepreferably 62 to 70% by weight, particularly preferably 64 to 68% byweight. When the fluorine content is in the above-defined range, thefluorine-containing copolymer has good solubility in solvents which willbe described later. The incorporation of the fluorine-containingcopolymer as a component can realize the formation of an opticallaminate having excellent adhesion, a high level of transparency, a lowrefractive index, and excellent mechanical strength.

The molecular weight of the fluorine-containing copolymer is preferably5,000 to 200,000, particularly preferably 10,000 to 100,000, in terms ofnumber average molecular weight as determined using polystyrene as astandard. When the fluorine-containing copolymer having this molecularweight is used, the fluororesin composition has suitable viscosity andthus reliably has suitable coatability.

The refractive index of the fluorine-containing copolymer per se ispreferably not more than 1.45, more preferably not more than 1.42, stillmore preferably not more than 1.40. When the refractive index is in theabove defined range, the formed optical laminate has good antireflectioneffect.

The addition amount of the resin is 30 to 150 parts by weight,preferably 35 to 100 parts by weight, more preferably 40 to 70 parts byweight, based on 100 parts by weight of the fluorine-containingcopolymer. The content of fluorine based on the total amount of thepolymer forming component comprising the fluorine-containing copolymerand the resin is 30 to 55% by weight, preferably 35 to 50% by weight.

When the addition amount or the fluorine content is in the above-definedrange, the surface modifying layer has good adhesion to the basematerial and has a low refractive index, whereby good antireflectioneffect can be attained.

In a preferred embodiment of the present invention, the utilization of“void-containing fine particles” as a low-refractive index agent ispreferred. “Void-containing fine particles” can lower the refractiveindex while maintaining the layer strength of the surface modifyinglayer. In the present invention, the term “void-containing fineparticle” refers to a fine particle which has a structure comprising airfilled into the inside of the fine particle and/or an air-containingporous structure and has such a property that the refractive index islowered in reverse, proportion to the proportion of air which occupiesthe fine particle as compared with the refractive index of the originalfine particle. Further, such a fine particle which can form a nanoporousstructure in at least a part of the inside and/or surface of the coatingfilm by utilizing the form, structure, aggregated state, and dispersedstate of the fine particle within the coating film, is also embraced inthe present invention.

Specific examples of preferred void-containing inorganic fine particlesare silica fine particles prepared by a technique disclosed in JapanesePatent Laid-Open No. 233611/2001. The void-containing silica fineparticles can easily produced. Further, the hardness of thevoid-containing fine particles is high. Therefore, when a surfacemodifying layer is formed by using a mixture of the void-containingsilica fine particles with a binder, the layer has improved strengthand, at the same time, the refractive index can be regulated to a rangeof approximately 1.20 to 1.45. Hollow polymer fine particles produced byusing a technique disclosed in Japanese Patent Laid-Open No. 80503/2002are a specific example of preferred void-containing organic fineparticles.

Fine particles which can form a nanoporous structure in at least a partof the inside and/or surface of the coating film include, in addition tothe above silica fine particles, sustained release materials, which havebeen produced for increasing the specific surface area and adsorbvarious chemical substances on a packing column and the porous part ofthe surface, porous fine particles used for catalyst fixation purposes,or dispersions or aggregates of hollow fine particles to be incorporatedin heat insulating materials or low-dielectric materials. Specificexamples of such fine particles include commercially available products,for example, aggregates of porous silica fine particles selected fromtradename Nipsil and tradename Nipgel manufactured by Nippon SilicaIndustrial Co., Ltd. and colloidal silica UP series (tradename),manufactured by Nissan Chemical Industries Ltd., having such a structurethat silica fine particles have been connected to one another in a chainform, and fine particles in a preferred particle diameter rangespecified in the present invention may be selected from the above fineparticles.

The average particle diameter of the “void-containing fine particles” isnot less than 5 nm and not more than 300 nm. Preferably, the lower limitof the average particle diameter is 8 nm, and the upper limit of theaverage particle diameter is 100 nm. More preferably, the lower limit ofthe average particle diameter is 10 nm, and the upper limit of theaverage particle diameter is 80 nm. When the average diameter of thefine particles is in the above-defined range, excellent transparency canbe imparted to the surface modifying layer.

2) High-refractive Index Agent/medium-refractive Index Agent

The high-refractive index agent and the medium-refractive index agentmay be added to the surface modifying layer to further improveantireflective properties. The refractive index of the high-refractiveindex agent and medium-refractive index agent may be set in a range of1.46 to 2.00. The medium-refractive index agent has a refractive indexin the range of 1.46 to 1.80, and the refractive index of thehigh-refractive index agent is in the range of 1.65 to 2.00.

These refractive index agents include fine particles, and specificexamples thereof (the numerical value within the parentheses being arefractive index) include zinc oxide (1.90), titania (2.3 to 2.7), ceria(1.95), tin-doped indium oxide (1.95), antimony-doped tin oxide (1.80),yttria (1.87), and zirconia (2.0).

Leveling Agent

A leveling agent may be added to the surface modifying layer. Preferredleveling agents include fluorine-type or silicone-type leveling agents.The surface modifying layer to which the leveling agent has been addedcan realize a good coated face, can effectively prevent the inhibitionof curing of the coating film surface by oxygen in coating or drying,and can impart a scratch resistance.

Contamination Preventive Agent

A contamination preventive agent may be added to the surface modifyinglayer. The contamination preventive agent is mainly used to prevent, thecontamination of the outermost surface of the optical laminate and canimpart scratch resistance to the optical laminate. Specific examples ofeffective contamination preventive agents include additives which candevelop water repellency, oil repellency, and fingerprint wiping-offproperties. More specific examples of contamination preventive agentsinclude fluorocompounds and silicon compounds or mixtures of thesecompounds. More specific examples thereof include fluoroalkylgroup-containing silane coupling agents such as2-perfluorooctylethyltriaminosilane. Among them, amino group-containingcompounds are particularly preferred.

Resin

The surface modifying layer may comprises at least a surface modifyingagent and a resin (including a resin component such as a monomer and anoligomer). When the surface modifying layer does not contain a surfacemodifying agent, the resin functions as a curability enhancing agent orfunctions to render the concavoconvexes of the anti-dazzling layersmooth.

The resin is preferably transparent, and specific examples thereof areclassified into ionizing radiation curing resins which are curable uponexposure to ultraviolet light or electron beams, mixtures of ionizingradiation curing resins with solvent drying-type resins, or heat curingresins. Preferred are ionizing radiation curing resins.

Specific examples of ionizing radiation curing resins include thosecontaining an acrylate-type functional group, for example, oligomers orprepolymers and reactive diluents, for example, relatively low-molecularweight polyester resins, polyether resins, acrylic resins, epoxy resins,urethane resins, alkyd resins, spiroacetal resins, polybutadiene resins,and polythiol polyene resins and (meth)acrylates of polyfunctionalcompounds such as polyhydric alcohols. Specific examples thereof includemonofunctional monomers such as ethyl (meth)acrylate, ethylhexyl(meth)acrylate, styrene, methyl styrene, and N-vinylpyrrolidone, andpolyfunctional monomers, for example, polymethylolpropanetri(meth)acrylate, hexanediol (meth)acrylate, tripropylene glycoldi(meth)acrylate, diethylene glycol di(meth)acrylate, pentaerythritoltri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,6-hexanedioldi(meth)acrylate, and neopentyl glycol di(meth)acrylate.

When the ionizing radiation curing resin is an ultraviolet curing resin,a photopolymerization initiator is preferably used. Specific examples ofphotopolymerization initiators include acetophenones, benzophenones,Michler's benzoyl benzoate, α-amyloxime ester, and thioxanthones.Preferably, photosensitizers are mixed in the system. Specific examplesof photosensitizers include n-butylamine, triethylamine, andpoly-n-butylphosphine.

When ionizing radiation curing resins are used as an ultraviolet curingresin, a photopolymerization initiator or a photopolymerizationaccelerator may be added. In the case of a radical polymerizableunsaturated group-containing resin system, acetophenones, benzophenones,thioxanthones, benzoins, benzoin methyl ether and the like are used as aphotopolymerization initiator either solely or as a mixture of two ormore. On the other hand, in the case of a cation polymerizablefunctional group-containing resin system, aromatic diazonium salts,aromatic sulfonium salts, aromatic idonium salts, metallocene compounds,benzoinsulfonic esters and the like may be used as a photopolymerizationinitiator either solely or as a mixture of two or more. The amount ofthe photopolymerization initiator added is 0.1 to 10 parts by weightbased on 100 parts by weight of the ionizing radiation curingcomposition.

The solvent drying-type resin used as a mixture with the ionizingradiation curing resin is mainly a thermoplastic resin. Commonlyexemplified thermoplastic resins are usable. Specific examples ofpreferred thermoplastic resins include styrenic resins, (meth)acrylicresins, vinyl acetate resins, vinyl ether resins, halogen-containingresins, alicyclic olefinic resins, polycarbonate resins, polyesterresins, polyamide resins, cellulose derivatives, silicone resins, andrubbers or elastomers. The resin is generally noncrystalline and, at thesame time, is soluble in an organic solvent (particularly a commonsolvent which can dissolve a plurality of polymers and curablecompounds). Particularly preferred are resins having good moldability orfilm forming properties, transparency, and weathering resistance, forexample, styrenic resins, (meth)acrylic resins, alicyclic olefinicresins, polyester resins, cellulose derivatives (for example, celluloseesters).

The coating film defect of the coated face can be effectively preventedby adding a solvent drying-type resin. In a preferred embodiment of thepresent invention, when the light transparent base material is formed ofa cellulosic resin such as triacetylcellulose “TAC,” examples ofpreferred thermoplastic resins include cellulosic resins, for example,nitrocellulose, acetylcellulose, cellulose acetate propionate, andethylhydroxyethylcellulose.

Specific examples of heat curing resin include phenolic resins, urearesins, diallyl phthalate resins, melanin resins, guanamine resins,unsaturated polyester resins, polyurethane resins, epoxy resins,aminoalkyd resins, melamine-urea cocondensed resins, silicone resins,and polysiloxane resins. When the heat curing resin is used, ifnecessary, for example, curing agents such as crosslinking agents andpolymerization initiators, polymerization accelerators, solvents, andviscosity modifiers may be further added.

Polymerization Initiator

In the formation of a surface modifying layer, photopolymerizationinitiators may be used. Specific examples thereof include1-hydroxy-cyclohexyl-phenyl-ketone. This compound is commerciallyavailable, and examples of commercially available products includeIrgacure 184 (tradename, manufactured by Ciba Specialty Chemicals,K.K.).

Solvent

A composition for a surface modifying layer comprising the abovecomponents mixed with the solvent is utilized for surface modifyinglayer formation. Specific examples of solvents usable herein includealcohols such as isopropyl alcohol, methanol, and ethanol; ketones suchas methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone;esters such as methyl acetate, ethyl acetate, and butyl acetate;halogenated hydrocarbons; aromatic hydrocarbons such as toluene andxylene; or mixture thereof. Preferred are ketones and esters.

Method for Surface Modifying Layer Formation

The surface modifying layer may be formed by applying a composition fora surface modifying layer onto the anti-dazzling layer. The compositionfor a surface modifying layer may be formed by coating methods such asroll coating, Mayor bar coating, or gravure coating. After coating ofthe composition for a surface modifying layer, the coating is dried andcured by ultraviolet light irradiation. Specific examples of ultravioletlight sources include ultra-high-pressure mercury lamps, high-pressuremercury lamps, low-pressure mercury lamps, carbon arc lamps, black lightfluorescent lamps, and metal halide lamps. Regarding the wavelength ofthe ultraviolet light, a wavelength range of 190 to 380 nm may be used.Specific examples of electron beam sources include various electron beamaccelerators, for example, Cockcroft-Walton accelerators, van de Graaffaccelerators, resonance transformer accelerators, insulated coretransformer accelerators, linear accelerators, Dynamitron accelerators,and high-frequency accelerators.

Optional Layers

The optical laminate according to the present invention comprises alight transparent base material, an anti-dazzling layer, and an optionalsurface modifying layer. Optional layers such as an antistatic layer, alow-refractive index layer, and a contamination preventive layer may befurther provided. The low-refractive index layer preferably has a lowerrefractive index than the refractive index of the anti-dazzling layer orsurface modifying layer. The antistatic layer, low-refractive indexlayer, and contamination preventive layer may be formed by using acomposition prepared by mixing a resin and the like with an antistaticagent, a low-refractive index agent, a contamination preventive agent orthe like as described above in connection with the surface modifyinglayer. Accordingly, the antistatic agent, low-refractive index agent,contamination preventive agent, resin and the like may be the same asthose used in the formation of the surface modifying layer.

4. Light Transparent Base Material

The light transparent base material is preferably smooth and possessesexcellent heat resistance and mechanical strength. Specific examples ofmaterials usable for the light transparent base material formationinclude thermoplastic resins, for example, polyesters (polyethyleneterephthalate and polyethylene naphthalate), cellulose triacetate,cellulose diacetate, cellulose acetatebutyrate, polyamide, polyimide,polyethersulfone, polysulfone, polypropylene, polymethylpentene,polyvinyl chloride, polyvinylacetal, polyether ketone, polymethylmethacrylate, polycarbonate, and polyurethane. Preferred are polyesters(polyethylene terephthalate and polyethylene naphthalate) and cellulosetriacetate. Films of amorphous olefin polymers (cycloolefin polymers:COPs) having an alicyclic structure may also be mentioned as otherexamples of the light transparent base material. These films are basematerials using nobornene polymers, monocyclic olefinic polymers, cyclicconjugated diene polymers, vinyl alicyclic hydrocarbon polymer resinsand the like, and examples thereof include Zeonex and ZEONOR,manufactured by Zeon Corporation (norbornene resins), Sumilight FS-1700manufactured by Sumitomo Bakelite Co., Ltd., ARTON (modified norborneneresin) manufactured by JSR Corporation, APL (cyclic olefin copolymer)manufactured by Mitsui Chemicals Inc., Topas (cyclic olefin copolymer)manufactured by Ticona, and Optlet OZ-1000 series (alicyclic acrylicresins) manufactured by Hitachi Chemical Co., Ltd. Further, FV series(low birefringent index and low photoelastic films) manufactured byAsahi Kasei Chemicals Corporation are also preferred as base materialsalternative to triacetylcellulose.

In the present invention, preferably, these thermoplastic resins areused as a highly flexible thin film. Depending upon the form of usewhere curability are required, plate-like materials such as plates ofthese thermoplastic resins or glass plates are also usable.

The thickness of the light transparent base material is not less than 20μm and not more than 300 μm. Preferably, the upper limit of thethickness is 200 μm, and the lower limit of the thickness is 30 μm. Whenthe light transparent base material is a plate-like material, thethickness may be above the upper limit of the above-defined thicknessrange. In forming an anti-dazzling layer on the light transparent basematerial, the base material may be previously subjected to physicaltreatment such as corona discharge treatment or oxidation treatment ormay be previously coated with an anchoring agent or a coating materialknown as a primer from the viewpoint of improving the adhesion.

Utilization of Optical Laminate

The optical laminate produced by the process according to the presentinvention may be used in the following applications.

Polarizing Plate

In another embodiment of the present invention, there is provided apolarizing plate comprising a polarizing element and the opticallaminate according to the present invention. More specifically, there isprovided a polarizing plate comprising a polarizing element and theoptical laminate according to the present invention provided on thesurface of the polarizing element, the optical laminate being providedso that the surface of the optical laminate remote from theanti-dazzling layer faces the surface of the polarizing element.

The polarizing element may comprise, for example, polyvinyl alcoholfilms, polyvinylformal films, polyvinylacetal films, and ethylene-vinylacetate copolymer-type saponified films, which have been dyed withiodine or a dye and stretched. In the lamination treatment, preferably,the light transparent base material (preferably a triacetylcellulosefilm) is saponified from the viewpoint of increasing the adhesion orantistatic purposes.

Image Display Device

In a further embodiment of the present invention, there is provided animage display device. The image display device comprises a transmissiondisplay and a light source device for applying light to the transmissiondisplay from its back side. The optical laminate according to thepresent invention or the polarizing plate according to the presentinvention is provided on the surface of the transmission display. Theimage display device according to the present invention may basicallycomprise a light source device (backlight), a display element, and theoptical laminate according to the present invention. The image displaydevice is utilized in transmission display devices, particularly indisplays of televisions, computers, word processors and the like. Amongothers, the image display device is used on the surface of displays forhigh-definition images such as CRTs and liquid crystal panels.

When the image display device according to the present invention is aliquid crystal display device, light emitted from the light sourcedevice is applied through the lower side of the optical laminateaccording to the present invention. In STN-type liquid crystal displaydevices, a phase difference plate may be inserted into between theliquid crystal display element and the polarizing plate. If necessary,an adhesive layer may be provided between individual layers in theliquid crystal display device.

EXAMPLES

The following embodiments further illustrate the present invention.However, it should be noted that the contents of the present inventionare not limited by these embodiments. The “parts” and “%” are by massunless otherwise specified.

Compositions for respective layers constituting an optical laminate wereprepared according to the following formulations. The formulations aresummarized in Table 1.

Preparation of Composition for Anti-dazzling Layer

Composition 1 for Anti-dazzling Layer

Pentaerythritol triacrylate (PETA) (manufactured by Nippon Kayaku Co.,Ltd., refractive index 1.51) (20.28 parts by mass) as an ultravioletcuring resin, 8.62 parts by mass of DPHA (manufactured by Nippon KayakuCo., Ltd., refractive index 1.51) as an ultraviolet curing resin, 3.03parts by mass of an acrylic polymer (manufactured by Mitsubishi RayonCo., Ltd., molecular weight 75,000) as an ultraviolet curing resin, 1.86parts by mass of Irgacure 184 (manufactured by Ciba-Geigy Limited) as aphotocuring initiator, 0.31 part by mass of Irgacure 907 (manufacturedby Ciba-Geigy Limited) as a photocuring initiator, 6.39 parts by mass ofmonodisperse acrylic beads (manufactured by Nippon Shokubai Kagaku KogyoCo., Ltd., particle diameter 5.0 μm, refractive index 1.53) as lighttransparent fine particles, 0.013 part by mass of a silicone levelingagent 10-28 (manufactured by The Inctec Inc.), 47.60 parts by mass oftoluene, and 11.90 parts by mass of cyclohexanone were thoroughly mixedtogether to prepare a composition. This composition was filtered througha polypropylene filter having a pore diameter of 30 μm to preparecomposition 1 for an anti-dazzling layer.

Composition 2 for Anti-dazzling Layer

Composition 2 for an anti-dazzling layer was prepared in the same manneras in the composition 1 for an anti-dazzling layer, except that thelight transparent fine particles were changed to monodisperse acrylicbeads having a particle diameter of 9.5 μm (manufactured by NipponShokubai Kagaku Kogyo Co., Ltd., refractive index 1.53).

Composition 3 for Anti-dazzling Layer

Composition 3 for an anti-dazzling layer was prepared in the same manneras in the composition 1 for an anti-dazzling layer, except that thelight transparent fine particles were changed to monodisperse acrylicbeads having a particle diameter of 13.5 μm (manufactured by NipponShokubai Kagaku Kogyo Co., Ltd., refractive index 1.53).

Composition 4 for Anti-dazzling Layer

Pentaerythritol triacrylate (PETA) (manufactured by Nippon Kayaku Co.,Ltd., refractive index 1.51) (21.08 parts by mass) as an ultravioletcuring resin, 10.33 parts by mass of DPHA (manufactured by Nippon KayakuCo., Ltd., refractive index 1.51) as an ultraviolet curing resin, 3.24parts by mass of an acrylic polymer (manufactured by Mitsubishi RayonCo., Ltd., molecular weight 75,000) as an ultraviolet curing resin, 2.02parts by mass of Irgacure 184 (manufactured by Ciba-Geigy Limited) as aphotocuring initiator, 0.34 part by mass of Irgacure 907 (manufacturedby Ciba-Geigy Limited) as a photocuring initiator, 3.47 parts by mass ofmonodisperse acrylic beads (manufactured by Nippon Shokubai Kagaku KogyoCo., Ltd., particle diameter 13.5 μm, refractive index 1.53) as lighttransparent fine particles, 0.014 part by mass of a silicone levelingagent 10-28 (manufactured by The Inctec Inc.), 47.60 parts by mass oftoluene, and 11.90 parts by mass of cyclohexanone were thoroughly mixedtogether to prepare a composition. This composition was filtered througha polypropylene filter having a pore diameter of 30 μm to preparecomposition 4 for an anti-dazzling layer.

Composition 5 for Anti-dazzling Layer

Pentaerythritol triacrylate (PETA) (manufactured by Nippon Kayaku Co.,Ltd., refractive index 1.51) (21.88 parts by mass) as an ultravioletcuring resin, 12.03 parts by mass of DPHA (manufactured by Nippon KayakuCo., Ltd., refractive index 1.51) as an ultraviolet curing resin, 3.46parts by mass of an acrylic polymer (manufactured by Mitsubishi RayonCo., Ltd., molecular weight 75,000) as an ultraviolet curing resin, 2.19parts by mass of Irgacure 184 (manufactured by Ciba-Geigy Limited) as aphotocuring initiator, 0.37 part by mass of Irgacure 907 (manufacturedby Ciba-Geigy Limited) as a photocuring initiator, 6.39 parts by mass ofmonodisperse acrylic beads (manufactured by Nippon Shokubai Kagaku KogyoCo., Ltd., particle diameter 9.5 μm, refractive index 1.53) as lighttransparent fine particles, 0.015 part by mass of a silicone levelingagent 10-28 (manufactured by The Inctec Inc.), 47.60 parts by mass oftoluene, and 11.90 parts by mass of cyclohexanone were thoroughly mixedtogether to prepare a composition. This composition was filtered througha polypropylene filter having a pore diameter of 30 μm to preparecomposition 5 for an anti-dazzling layer.

Composition 6 for Anti-dazzling Layer

Composition 6 for an anti-dazzling layer was prepared in the same manneras in the composition 1 for an anti-dazzling layer, except that thelight transparent fine particles were changed to acrylic beads having aparticle size distribution of 5.0 μm in terms of particle diameter(manufactured by Nippon Shokubai Kagaku Kogyo Co., Ltd., refractiveindex 1.53).

Composition 7 for Anti-dazzling Layer

Pentaerythritol triacrylate (PETA) (manufactured by Nippon Kayaku Co.,Ltd., refractive index 1.51) (20.28 parts by mass) as an ultravioletcuring resin, 8.62 parts by mass of DPHA (manufactured by Nippon KayakuCo., Ltd., refractive index 1.51) as an ultraviolet curing resin, 3.03parts by mass of an acrylic polymer (manufactured by Mitsubishi RayonCo., Ltd., molecular weight 75,000) as an ultraviolet curing resin, 1.86parts by mass of Irgacure 184 (manufactured by Ciba-Geigy Limited) as aphotocuring initiator, 0.31 part by mass of Irgacure 907 (manufacturedby Ciba-Geigy Limited) as a photocuring initiator, 4.80 parts by mass ofmonodisperse acrylic beads (manufactured by Nippon Shokubai Kagaku KogyoCo., Ltd., particle diameter 9.5 μm, refractive index 1.53) as firstlight transparent fine particles, 1.59 parts by mass of monodisperseacrylic beads (manufactured by Nippon Shokubai Kagaku Kogyo Co., Ltd.,particle diameter 9.5 μm, refractive index 1.53) as second lighttransparent fine particles, 0.013 part by mass of a silicone levelingagent 10-28 (manufactured by The Inctec Inc.), 47.60 parts by mass oftoluene, and 11.90 parts by mass of cyclohexanone were thoroughly mixedtogether to prepare a composition. This composition was filtered througha polypropylene filter having a pore diameter of 30 μm to preparecomposition 7 for an anti-dazzling layer.

Composition 8 for Anti-dazzling Layer

Pentaerythritol triacrylate (PETA) (manufactured by Nippon Kayaku Co.,Ltd., refractive index 1.51) (21.28 parts by mass) as an ultravioletcuring resin, 8.63 parts by mass of DPHA (manufactured by Nippon KayakuCo., Ltd., refractive index 1.51) as an ultraviolet curing resin, 3.18parts by mass of an acrylic polymer (manufactured by Mitsubishi RayonCo., Ltd., molecular weight 75,000) as an ultraviolet curing resin, 1.96parts by mass of Irgacure 184 (manufactured by Ciba-Geigy Limited) as aphotocuring initiator, 0.33 part by mass of Irgacure 907 (manufacturedby Ciba-Geigy Limited) as a photocuring initiator, 4.96 parts by mass ofacrylic beads (manufactured by Nippon Shokubai Kagaku Kogyo Co., Ltd.,particle diameter 4.6 μm, refractive index 1.53) as first lighttransparent fine particles, 1.65 parts by mass of acrylic beads(manufactured by Nippon Shokubai Kagaku Kogyo Co., Ltd., particlediameter 3.5 μm, refractive index 1.53) as second light transparent fineparticles, 0.013 part by mass of a silicone leveling agent 10-28(manufactured by The Inctec Inc.), 46.40 parts by mass of toluene, and11.60 parts by mass of cyclohexanone were thoroughly mixed together toprepare a composition. This composition was filtered through apolypropylene filter having a pore diameter of 30 μm to preparecomposition 8 for an anti-dazzling layer.

Composition 9 for Anti-dazzling Layer

EXG40-77 (V-15M) (amorphous silica ink, average particle diameter ofsilica 2.5 μm, solid content 60%, manufactured by Dainichiseika Color &Chemicals Manufacturing Co., Ltd.) (1.77 g) as an amorphous silicamatting agent ink for an anti-dazzling layer, pentaerythritoltriacrylate (PETA) (manufactured by Nippon Kayaku Co., Ltd., refractiveindex 1.51) (2.93 g) as an ultraviolet curing resin, 0.37 g of anacrylic polymer (manufactured by Mitsubishi Rayon Co., Ltd., molecularweight 40,000) as an ultraviolet curing resin, 0.17 g of Irgacure 184(manufactured by Ciba-Geigy Limited) as a photocuring initiator, 0.6 gof Irgacure 907 (manufactured by Ciba-Geigy Limited) as a photocuringinitiator, 0.043 g of a silicone leveling agent 10-28 (manufactured byThe Inctec Inc.), 7.8 g of toluene, and 1.0 g of MIBK (methyl isobutylketone) were thoroughly mixed together to prepare a composition. Thiscomposition was filtered through a polypropylene filter having a porediameter of 80 μm to prepare composition 9 for an anti-dazzling layer.

Preperation of Composition for Surface Modifying Layer

Composition 1 for Surface Modifying Layer

DPHA (manufactured by Nippon Kayaku Co., Ltd., refractive index 1.51)(39.30 parts by mass) as an ultraviolet curing resin, 3.13 parts by massof an acrylic polymer (manufactured by Mitsubishi Rayon Co., Ltd.,molecular weight 40,000) as an ultraviolet curing resin, 2.12 parts bymass of Irgacure 184 (manufactured by Ciba-Geigy Limited) as aphotocuring initiator, 0.43 part by mass of Irgacure 907 (manufacturedby Ciba-Geigy Limited) as a photocuring initiator, 0.19 part by mass ofa silicone leveling agent 10-28 (manufactured by The Inctec Inc.), 49.35parts by mass of toluene, and 5.48 parts by mass of cyclohexanone werethoroughly mixed together to prepare a composition. This composition wasfiltered through a polypropylene filter having a pore diameter of 10 μmto prepare composition 1 for a surface modifying layer.

Composition 2 for Surface Modifying Layer

C-4456 S-7 (an ATO-containing electroconductive ink, average particlediameter of ATO 300 to 400 nm, solid content 45%, manufactured by NIPPONPELNOX CORP.) (21.6 g) as a material for an antistatic layer, 28.69 g ofDPHA (manufactured by Nippon Kayaku Co., Ltd., refractive index 1.51) asan ultraviolet curing resin, 1.56 g of Irgacure 184 (manufactured byCiba-Geigy Limited) as a photocuring initiator, 33.7 g of MIBK (methylisobutyl ketone), and 14.4 g of cyclohexanone were thoroughly mixedtogether to prepare a composition. This composition was filtered througha polypropylene filter having a pore diameter of 30 μm to preparecomposition 2 for a surface modifying layer.

Composition 3 for Surface Modifying Layer

Composition 3 for a surface modifying layer having the followingformulation was prepared using a zirconia-containing coating composition(tradename; “KZ 7973”, a resin matrix having a refractive index of 1.69,solid content 50%, manufactured by JSR) so that the resin matrix had arefractive index of 1.60.

Pentaerythritol triacrylate (PETA) (manufactured by Nippon Kayaku Co.,Ltd., refractive index 1.51) (18.59 parts by mass) as an ultravioletcuring resin, 17.18 parts by mass of zirconia (zirconia contained in “KZ7973” (tradename), average particle diameter 40 to 60 nm, refractiveindex 2.0, manufactured by JSR) for incorporation in an ultravioletcuring resin to develop a resin matrix, 1.22 parts by mass of a zirconiadispersant (a zirconia dispersion stabilizer contained in “KZ 7973”(tradename), manufactured by JSR), 0.94 part by mass of an acrylicpolymer (manufactured by Mitsubishi Rayon Co., Ltd., molecular weight40,000) as an ultraviolet curing resin, 1.56 parts by mass of Irgacure184 (manufactured by Ciba-Geigy Limited) as a photocuring initiator,0.26 part by mass of Irgacure 907 (manufactured by Ciba-Geigy Limited)as a photocuring initiator, 0.039 part by mass of a silicone levelingagent 10-28 (manufactured by The Inctec Inc.), 14.34 parts by mass oftoluene, 15.76 parts by mass of cyclohexanone, and 2.80 parts by mass ofMEK were thoroughly mixed together to prepare a composition. Thiscomposition was filtered through a polypropylene filter having a porediameter of 30 μm to prepare composition 3 for a surface modifyinglayer.

Preparation of Composition for Low-refractive Index Layer

Composition 1 for Low-refractive Index Layer

A photopolymerization initiator (tradename; “JUA701,” manufactured byJSR) (0.85 g) and 65 g of MIBK were added to 34.14 g of a fluororesincomposition (tradename; “TM086”, manufactured by JSR), and the mixturewas stirred and was filtered through a polypropylene filter having apore diameter of 10 μm to prepare composition for a low-refractive indexlayer.

Composition 2 for Low-refractive Index Layer

The following components were stirred according to the followingformulation, and the mixture was filtered through a polypropylene filterhaving a pore diameter of 10 μm to prepare composition 2 for alow-refractive index layer.

Surface treated silica sol (void-containing 14.3 pts. wt. fineparticles) (as 20% methyl isobutyl ketone solution) Pentaerythritoltriacrylate 1.95 pts. wt. (PETA, refractive index 1.51, manufactured byNippon Kayaku Co., Ltd.) Irgacure 907 (manufactured by Ciba  0.1 pt. wt.Specialty Chemicals, K.K.) Polyether-modified silicone oil TSF4460 0.15pt. wt. (tradename, manufactured by GE Toshiba Silicone Co., Ltd.)Methyl isobutyl ketone 83.5 pts. wt.

Preparation of Composition for Antistatic Layer

C-4456 S-7 (an ATO-containing electroconductive ink, average particlediameter of ATO 300 to 400 nm, solid content 45%, manufactured by NIPPONPELNOX CORP.) (2.0 g) was provided as a material for an antistaticlayer. Methyl isobutyl ketone (2.84 g) and 1.22 g of cyclohexanone wereadded to the material, and the mixture was stirred and was filteredthrough a polypropylene filter having a pore diameter of 30 μm toprepare composition for an antistatic layer.

Production of Optical Laminate

Example 1

An optical laminate according to the present invention was produced asfollows to produce an optical laminate (HG1).

Formation of Anti-dazzling Layer

An 80 μm-thick triacetylcellulose film (TD80U, manufactured by FujiPhoto Film Co., Ltd.) was provided as a transparent base material.Composition 1 for an anti-dazzling layer was coated onto the transparentbase material with a wire-wound rod for coating (Mayer's bar), and thecoated transparent base material was heat dried in an oven of 70° C. forone min to evaporate the solvent component. Thereafter, under nitrogenpurge (oxygen concentration: not more than 200 ppm), ultraviolet lightwas applied at an exposure of 30 mJ for half curing to cure the coatingfilm. Thus, a 5 μm-thick anti-dazzling hardcoat layer was formed. Thelight transparent fine particles were monodisperse acrylic beads havinga particle diameter of 5.0 μm.

Formation of Surface Modifying Layer

Composition 1 for a surface modifying layer was coated onto theanti-dazzling layer with a wire-wound rod for coating (Mayer's bar), andthe coating was heat dried in an oven of 70° C. for one min to evaporatethe solvent component. Thereafter, under nitrogen purge (oxygenconcentration: not more than 200 ppm), ultraviolet light was applied atan exposure of 100 mJ to cure the coating film. Thus, a 3 μm-thicksurface modifying layer was formed.

Example 2

An optical laminate (HG2) was produced in the same manner as in Example1, except that composition 2 for an anti-dazzling layer was used. Thelight transparent fine particles in composition 2 for an anti-dazzlinglayer were monodisperse acrylic beads having a particle diameter of 9.5μm, and the surface modifying layer had a thickness of 4.0 μm.

Example 3

An optical laminate (HG3) was produced in the same manner as in Example1, except that composition 3 for an anti-dazzling layer was used. Thelight transparent fine particles in composition 3 for an anti-dazzlinglayer were monodisperse acrylic beads having a particle diameter of 13.5

Example 4

An optical laminate was produced in the same manner as in Example 1,except that composition 4 for an anti-dazzling layer was used. The lighttransparent fine particles in composition 4 for an anti-dazzling layerwere monodisperse acrylic beads having a particle diameter of 13.5 μm,and the proportion of the light transparent fine particles to the totalweight of the solid content was ½ in the case of Example 3.

Example 5

An optical laminate was produced in the same manner as in Example 1,except that composition 5 for an anti-dazzling layer was used. The lighttransparent fine particles in composition 5 for an anti-dazzling layerwere monodisperse acrylic beads having a particle diameter of 9.5 μm,and the proportion of the light transparent fine particles to the totalweight of the solid content was 75/1000 in the case of Example 2.

Example 6

An optical laminate was produced in the same manner as in Example 1,except that composition 6 for an anti-dazzling layer was used. The lighttransparent fine particles in composition 6 for an anti-dazzling layerwere acrylic beads having a particle size distribution of 5.0 μm.

Example 7

An optical laminate was produced in the same manner as in Example 1,except that composition 7 for an anti-dazzling layer was used. The firstlight transparent fine particles in composition 7 for an anti-dazzlinglayer were monodisperse acrylic beads having a particle diameter of 9.5μm, and the second light transparent fine particle were monodisperseacrylic beads having a particle diameter of 5.0 μm.

Example 8

An optical laminate was produced in the same manner as in Example 1,except that composition 4 for an anti-dazzling layer and composition 2for a surface modifying layer were used. In order to form anelectroconductive surface modifying layer, an ATO-containing compositionwas used in composition 2 for a surface modifying layer. The opticallaminate had an electrical surface resistance value of 2.0×10¹²Ω/□.

Example 9

An optical laminate according to the present invention was produced asfollows to produce an optical laminate.

Formation of Antistatic Layer

An 80 μm-thick triacetylcellulose film (TD80U, manufactured by FujiPhoto Film Co., Ltd.) was provided as a light transparent base material.The composition for an antistatic layer was coated onto the lighttransparent base material with a wire-wound rod for coating (Mayer'sbar), and the coated light transparent base material was heat dried inan oven of 50° C. for one min to evaporate the solvent component.Thereafter, under nitrogen purge (oxygen concentration: not more than200 ppm), ultraviolet light was applied at an exposure of 30 mJ for halfcuring to cure the coating film. Thus, a 1 μm-thick antistatic layer wasformed.

Formation of Anti-dazzling Layer

Composition 4 for an anti-dazzling layer was coated onto the antistaticlayer with a wire-wound rod for coating (Mayer's bar), and the coatingwas heat dried in an oven of 70° C. for one min to evaporate the solventcomponent. Thereafter, under nitrogen purge (oxygen concentration: notmore than 200 ppm), ultraviolet light was applied at an exposure of 30mJ for half curing to cure the coating film. Thus, a 3 μm-thickanti-dazzling layer was formed.

Formation of Surface Modifying Layer

Composition 1 for a surface modifying layer was coated onto theanti-dazzling layer with a wire-wound rod for coating (Mayer's bar), andthe coating was heat dried in an oven of 70° C. for one min to evaporatethe solvent component. Thereafter, under nitrogen purge (oxygenconcentration: not more than 200 ppm), ultraviolet light was applied atan exposure of 100 mJ to cure the coating film. Thus, a 3 μm-thicksurface modifying layer was formed to produce an optical laminate. Theelectrical surface resistance value of the optical laminate was3.2×10¹²Ω/□.

Example 10

An optical laminate according to the present invention was produced asfollows. An anti-dazzling layer was formed in the same manner as inExample 1, except that, in forming an anti-dazzling layer, composition 4for an anti-dazzling layer was used. Further, a surface modifying layerwas formed in the same manner as in Example 1, except that ultravioletlight was applied at an exposure of 30 mJ for half curing to cure thecoating film.

Formation of Low-refractive Index Layer

Composition 2 for a low-refractive index layer was coated onto theanti-dazzling layer with a wire-wound rod for coating (Mayer's bar), andthe coating was heat dried in an oven of 50° C. for one min to evaporatethe solvent component. Thereafter, under nitrogen purge (oxygenconcentration: not more than 200 ppm), ultraviolet light was applied atan exposure of 150 mJ to cure the coating film. Thus, a 98 μm-thicksurface modifying layer was formed to produce an optical laminate.

Example 11

An optical laminate according to the present invention produced asfollows. An optical laminate was produced in the same manner as inExample 10, except that, in forming a surface modifying layer,composition 3 for a surface modifying layer and composition 1 for alow-refractive index layer were used. A zirconia-containing resin matrixwas used in composition 3 for a surface modifying layer, and therefractive index of the surface modifying layer was regulated to 1.60

Example 12 Embossing Method

Preparation of Emboss Roller

An iron roller was provided. 100-mesh (particle size distribution; 106μm to 150 μm) glass beads were shot against the surface of the roller toform concavoconcaves. The concavoconvex face was plated with chromium toa thickness of 5 μm to prepare an emboss roller. In bead shot blasting,blasting pressure, the spacing between the blasting nozzle and theroller and the like were regulated to prepare an emboss roller whichcorresponds to optical characteristics of the concavoconvex shape in theanti-dazzling layer provided in the optical laminate according to thepresent invention.

Preparation of Composition for Anti-Dazzling Layer

A composition prepared by mixing a polyurethane resin primer coatingmaterial (a medium main agent for chemical mat varnish, curing agent(XEL curing agent (D), manufactured by The Inctec Inc.) in a mass ratioof main agent to curing agent to solvent of 10:1:3.3 was gravure coated,and the coating was dried to form a 3 μm-thick primer layer.

The solvent used was a mixed solvent composed of toluene and methylethyl ketone in a ratio of 1:1.

Production of Optical Laminate

A fourth production apparatus (an embossing apparatus 40) according tothe present invention is shown in FIG. 6. The emboss roller preparedabove was mounted on the embossing apparatus, and the composition for ananti-dazzling layer was supplied into a liquid reservoir in a coatinghead. An 80 μm-thick polyethylene terephthalate resin film (the stocknumber; A4300, manufactured by Toyobo Co., Ltd.) was provided andsupplied to the emboss roller. The composition for an anti-dazzlinglayer was coated onto the emboss roller and was then applied onto thepolyethylene terephthalate film. Subsequently, ultraviolet light from anultraviolet light source (D-bulb, manufactured by Fusion) was applied tothe coating from the film side, and the assembly was then separated toproduce an optical laminate according to the present invention.

Comparative Example 1

A conventional anti-dazzling optical laminate was prepared as follows toproduce an optical laminate (AG1). Specifically, an 80 μm-thicktriacetylcellulose film (TD80U, manufactured by Fuji Photo Film Co.,Ltd.) was provided as a transparent base material. Composition 8 for ananti-dazzling layer was coated onto the transparent base material with awire-wound rod for coating (Mayer's bar), and the coated transparentbase material was heat dried in an oven of 70° C. for one min toevaporate the solvent component. Thereafter, under nitrogen purge(oxygen concentration: not more than 200 ppm), ultraviolet light wasapplied at an exposure of 100 mJ to cure the coating film. Thus, a 6μm-thick anti-dazzling hardcoat layer was formed. AG1 is ananti-dazzling optical laminate (AG1) of a mixed particle system using4.96 parts by mass of acrylic beads (manufactured by Nippon ShokubaiKagaku Kogyo Co., Ltd., particle diameter 4.6 μm, refractive index 1.53)as first light transparent fine particles and 1.65 parts by mass ofacrylic beads (manufactured by Nippon Shokubai Kagaku Kogyo Co., Ltd.,particle diameter 3.5 μm, refractive index 1.53) as second lighttransparent fine particles.

Comparative Example 2

A conventional anti-dazzling optical laminate was produced as follows toproduce an optical laminate. Specifically, the procedure of ComparativeExample 1 was repeated, except that composition 9 for an anti-dazzlinglayer was used and the thickness of the anti-dazzling layer was 3 μm.The optical laminate of Comparative Example 2 is an anti-dazzlingoptical laminate (AG) using amorphous silica.

Evaluation Test

The following evaluation tests were carried out. The results are shownin FIGS. 7 to 9 and Table 1 (results of evaluations 3 to 6).

Evaluation 1: Planar Shape Evaluation Test

Each of the optical laminates of Example and Comparative Example wasmounted on a panel of an image display device, and the surface shape wasphotographed with an optical microscope (tradename; BX60-F3,manufactured by OLYMPUS; 200 times). The results were as shown in FIG.7. As can be seen from FIG. 7, for HG1 to HG3 which are opticallaminates according to the present invention, the waviness of theconcavoconvex shape was smooth, the concavoconvex shape is not sharp,and the whole surface is in the form of a plurality of very gentlysloping hills. On the other hand, for AG1 which is a conventionalanti-dazzling optical laminate, the surface is rough like an enlargedphotograph of the human skin, and the concavoconvex shape is sharp.

Evaluation 2: Three-dimensionality Evaluation Test for ConcavoconvexShape

Each of the optical laminates of Example and Comparative Example wasmounted on a panel of an image display device, and the surface shape wasphotographed with AFM (tradename: a scanning probe microscope). Theresults were as shown in FIGS. 8 and 9. As can be seen from FIG. 8, forHG1 to HG3 which are optical laminates according to the presentinvention, the waviness of the concavoconvex shape was very smooth, theconcavoconvex shape is not sharp, and the whole surface is in the formof a plurality of very gently sloping hills. On the other hand, as canbe seen from FIG. 9, for AG1 which is a conventional anti-dazzlingoptical laminate, the surface is in the form of a number of sharpconcavoconvex shapes.

Evaluation 3: Optical Characteristics Test

For the optical laminates of Example and Comparative Example, the hazevalue (%), 60-degree gloss, Sm, θa, Rz, reflection Y value (5-degreereflection), and electrical surface resistance were measured accordingto the definition described in the present specification. The resultswere as shown in Table 1.

Evaluation 4: Glossy Black Feeling Test

A crossed Nicol polarizing plate was applied onto each of the opticallaminates of Example and Comparative Example on its side remote from thefilm. Sensory evaluation was carried out under three-wavelengthfluorescence, and glossy black feeling (reproduction of glossy black)was evaluated in detail according to the following criteria.

Evaluation Criteria

◯: Glossy black could be reproduced.

Δ: Glossy black could be somewhat reproduced but was unsatisfactory as aproduct.

x: Glossy back could not be reproduced.

Evaluation 5: Glare Test

A black matrix pattern plate (105 ppi) formed on a 0.7 mm-thick glasswas placed on a viewer manufactured by HAKUBA (light viewer 7000PRO) sothat the pattern surface faced downward. The optical laminate filmprepared above was placed thereon so that the concavoconvex face was onthe air side. Glare was visually observed in a dark room while lightlypressing with a finger the edge of the film to prevent the lift of thefilm, and the results were evaluated.

Evaluation criteria

◯: No glare was observed at 105 ppi, and the antiglareness was good.

x: Glare was observed at 105 ppi, and the antiglareness was poor.

Evaluation 6: Anti-dazzling Evaluation Test

A black acrylic plate was applied onto the backside of the opticallaminate with the aid of an optical pressure-sensitive adhesive. Thesample was placed on a horizontal desk. White fluorescent lamps (32 W×2lamps) were disposed 2.5 m above the desk. Reflection of the edge partof the white fluorescent lamps was visually observed and was evaluated.

Evaluation criteria

◯: The edge was not reflected, and the anti-dazzling property was good.

x: The edge was reflected, and the anti-dazzling property was poor.

TABLE 1 Composition for anti-dazzling layer Solvent Light transparentfine particles Binder composition Weight ratio Addition (Ratio of perunit area amount of toluene to between polymer coating Particle resinand (based on Monomer composition diameter Material particle binder)ratio component) Ex. 1 5.0 μm PMMA 0.20 PMMA PETA: Toluene: polymer DPHA= cyclohexanone = 10 wt % 65:35 80:20 wt % (mw 75000) wt % (40.5 wet %)Ex. 2 9.5 μm ↓ ↓ ↓ ↓ ↓ Ex. 3 13.5 μm  ↓ ↓ ↓ ↓ ↓ Ex. 4 13.5 μm  ↓ 0.10 ↓↓ ↓ Ex. 5 9.5 μm ↓ 0.015 ↓ ↓ ↓ Ex. 6 5.0 ± 2.0 ↓ 0.20 ↓ ↓ ↓ (particlesize distribution) Ex. 7 9.5 μm ↓ 0.20 ↓ ↓ ↓ 5.0 μm (9.5 μm . . . 0.15Mixed 5.0 μm . . . 0.05) particle system Ex. 8 13.5 μm  ↓ 0.10 ↓ ↓ ↓ Ex.9 ↓ ↓ ↓ ↓ ↓ ↓ Ex. 10 ↓ ↓ ↓ ↓ ↓ ↓ Ex. 11 ↓ ↓ ↓ ↓ ↓ ↓ Ex. 12Concavo-convex formation by embossing (embossing treatment) Comp. 4.6 μm↓ 0.18 ↓ ↓ ↓ Ex. 1 3.5 μm Mixed particle system Comp. Average Silica0.00 PMMA PETA = Toluene: Ex. 2 particle polymer 100 MIBK = diameter1.25 wt % 90:10 wt % 2.5 μm (mw 45000) (40.5 wet %) Amorphous silicaEvaluation 3 Reflection 60- Y value Haze degree (5-degree Evalua-Evalua- Evalua- (%) gloss Sm θa Rz reflection) tion 4 tion 5 tion 6 Ex.1 0.3 98.7 233.1 0.384 0.606 — ∘ ∘ ∘ (* No low- refractive index layer:4%) Ex. 2 0.4 94.6 170.2 0.504 0.663 — ∘ ∘ ∘ Ex. 3 0.6 90.3 362.5 0.5391.040 — ∘ ∘ ∘ Ex. 4 0.5 92.3 354.1 0.478 0.833 — ∘ ∘ ∘ Ex. 5 0.4 94.8375.1 0.422 0.482 — ∘ ∘ ∘ Ex. 6 0.4 93.2 192.3 0.621 0.834 — ∘ ∘ ∘ Ex. 70.5 94.9 201.3 0.532 0.743 — ∘ ∘ ∘ Ex. 8 1.4 93.2 323.1 0.912 0.893 — ∘∘ ∘ Ex. 9 1.8 93.1 367.3 0.623 0.982 — ∘ ∘ ∘ Ex. 10 0.5 65.3 392.3 0.4320.732 1.8% ∘ ∘ ∘ Ex. 11 1.3 56.2 245.3 0.392 0.652 1.4% ∘ ∘ ∘ Ex. 12 1.970.3 102.2 0.493 0.832 ∘ ∘ ∘ Comp. 4.7 48.2 93.2 1.892 1.439 — x x ∘ Ex.1 Comp. 3.8 65.0 267.2 1.857 1.932 — x ∘ x Ex. 2

1. An optical laminate comprising a light transparent base material andan anti-dazzling layer provided on the light transparent base material,said optical laminate being produced by a process comprising: providingthe light transparent base material; and forming the anti-dazzling layerhaving a concavoconvex shape on the light transparent base material,wherein the concavoconvex shape of the anti-dazzling layer satisfies thefollowing requirements: Sm is not less than 100 μm and not more than 600μm, θa is not less than 0.1 degree and not more than 1.2 degrees, and Rzis more than 0.2 μm and not more than 1.2 μm, wherein Sm represents theaverage spacing of concavoconvexes in the anti-dazzling layer; θarepresents the average inclination angle of the concavoconvexes; and Rzrepresents the average roughness of the concavoconvexes.
 2. The opticallaminate according to claim 1, wherein the step of forming theanti-dazzling layer comprises forming an anti-dazzling layer with aconcavoconvex shape previously formed therein on the light transparentbase material.
 3. The optical laminate according to claim 1, wherein thestep of forming the anti-dazzling layer comprises forming ananti-dazzling layer on the light transparent base material and formingconcavoconvexes on the surface of the anti-dazzling layer.
 4. Theoptical laminate according to claim 3, wherein the step of forming theconcavoconvexes comprises embossing treatment using a mold having areversed concavoconvex shape in relation to the concavoconvex shape inthe anti-dazzling layer.
 5. The optical laminate according to claim 1,wherein the step of forming the anti-dazzling layer comprises applying acomposition for an anti-dazzling layer onto the light transparent basematerial to form an anti-dazzling layer having the concavoconvex shape.6. The optical laminate according to claim 5, wherein the compositionfor an anti-dazzling layer comprises a resin and fine particles.
 7. Theoptical laminate according to claim 6, wherein the fine particles areaggregation-type fine particles.
 8. The optical laminate according toclaim 7, wherein the aggregation-type fine particles are a plurality oftypes of fine particles which are identical to or different from eachother in average particle diameter.
 9. The optical laminate according toclaim 5, wherein the composition for an anti-dazzling layer does notcontain fine particles and comprises a mixture of at least one polymerwith at least one curable resin precursor.
 10. An optical laminatecomprising a light transparent base material and an anti-dazzling layerprovided on the light transparent base material, said optical laminatebeing produced by an apparatus comprising: a feed part for feeding thelight transparent base material and the anti-dazzling layer having aconcavoconvex shape; and a forming part for forming the anti-dazzlinglayer on the light transparent base material, wherein the concavoconvexshape of the anti-dazzling layer satisfies the following requirements:Sm is not less than 100 μm and not more than 600 μm, θa is not less than0.1 degree and not more than 1.2 degrees, and Rz is more than 0.2 μm andnot more than 1.2 μm, wherein Sm represents the average spacing ofconcavoconvexes in the anti-dazzling layer; θa represents the averageinclination angle of the concavoconvexes; and Rz represents the averageroughness of the concavoconvexes.
 11. The optical laminate according toclaim 10, which further comprises a second forming part for forming asurface modifying layer on the surface of the concavoconvex shape of theanti-dazzling layer after the anti-dazzling layer formation.
 12. Theoptical laminate according to claim 1, wherein Rz is more than 0.2 μmand not more than 1.0 μm.
 13. The optical laminate according to claim10, wherein Rz is more than 0.2 μm and not more than 1.0 μm.